diff --git a/Gruntfile.js b/Gruntfile.js
index 7e99ae9183..2c213492a8 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -26,13 +26,16 @@ module.exports = function(grunt) {
 				processors: [
 					autoprefixer({
 						browsers: [
-							'Android >= 2.1',
-							'Chrome >= 21',
-							'Edge >= 12',
-							'Explorer >= 7',
-							'Firefox >= 17',
-							'Opera >= 12.1',
-							'Safari >= 6.0'
+							'> 1%',
+							'ie >= 11',
+							'last 1 Android versions',
+							'last 1 ChromeAndroid versions',
+							'last 2 Chrome versions',
+							'last 2 Firefox versions',
+							'last 2 Safari versions',
+							'last 2 iOS versions',
+							'last 2 Edge versions',
+							'last 2 Opera versions'
 						],
 						cascade: false
 					})
diff --git a/src/wp-admin/css/about.css b/src/wp-admin/css/about.css
index 711ac46fdc..521209f67b 100644
--- a/src/wp-admin/css/about.css
+++ b/src/wp-admin/css/about.css
@@ -51,7 +51,6 @@
 .wp-badge {
 	background: #0073aa url(../images/w-logo-white.png?ver=20160308) no-repeat;
 	background-position: center 25px;
-	-webkit-background-size: 80px 80px;
 	background-size: 80px 80px;
 	color: #fff;
 	font-size: 14px;
@@ -63,7 +62,6 @@
 	display: inline-block;
 	width: 140px;
 	text-rendering: optimizeLegibility;
-	-webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.2);
 	box-shadow: 0 1px 3px rgba(0,0,0,0.2);
 }
 
@@ -161,23 +159,12 @@
 /* 1.2 - Structure */
 
 .about-wrap [class$="-col"] {
-	display: -ms-flexbox;
-	display: -webkit-flex;
 	display: -webkit-box;
-	display: -moz-box;
 	display: flex;
 	-webkit-box-pack: justify;
-	-webkit-justify-content: space-between;
-	-moz-box-pack: justify;
-	-ms-flex-pack: justify;
 	justify-content: space-between;
 	-webkit-box-align: center;
-	-webkit-align-items: center;
-	-moz-box-align: center;
-	-ms-flex-align: center;
 	align-items: center;
-	-webkit-flex-wrap: wrap;
-	-ms-flex-wrap: wrap;
 	flex-wrap: wrap;
 }
 
@@ -187,10 +174,7 @@
 }
 
 .about-wrap [class$="-col"] .col {
-	-webkit-flex: 1;
-	-ms-flex: 1;
 	-webkit-box-flex: 1;
-	-moz-box-flex: 1;
 	flex: 1;
 }
 
@@ -201,7 +185,6 @@
 
 .about-wrap .three-col .col {
 	-webkit-align-self: flex-start;
-	-ms-flex-item-align: start;
 	align-self: flex-start;
 	min-width: 31%;
 	max-width: 31%;
@@ -260,10 +243,8 @@
 
 .about-wrap .two-col-text {
 	-webkit-column-count: 2;
-	-moz-column-count: 2;
 	column-count: 2;
 	-webkit-column-gap: 40px;
-	-moz-column-gap: 40px;
 	column-gap: 40px;
 }
 
@@ -448,7 +429,6 @@
 @media screen and ( max-width: 782px ) {
 	.about-wrap .two-col-text {
 		-webkit-column-count: 1;
-		-moz-column-count: 1;
 		column-count: 1;
 	}
 
diff --git a/src/wp-admin/css/admin-menu.css b/src/wp-admin/css/admin-menu.css
index 74b922ec47..a1f6919004 100644
--- a/src/wp-admin/css/admin-menu.css
+++ b/src/wp-admin/css/admin-menu.css
@@ -47,7 +47,6 @@
 	display: inline-block;
 	-webkit-font-smoothing: antialiased;
 	-moz-osx-font-smoothing: grayscale;
-	-webkit-transition: all .1s ease-in-out;
 	transition: all .1s ease-in-out;
 }
 
@@ -203,7 +202,6 @@
 	padding: 7px 0 8px;
 	z-index: 9999;
 	background-color: #32373c;
-	-webkit-box-shadow: 0 3px 5px rgba(0,0,0,0.2);
 	box-shadow: 0 3px 5px rgba(0,0,0,0.2);
 }
 
@@ -227,7 +225,6 @@
 	bottom: auto;
 	border: 0 none;
 	margin-top: 0;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	background-color: #32373c;
 }
@@ -301,7 +298,6 @@
 .folded #adminmenu .wp-has-current-submenu li > a {
 	padding-right: 16px;
 	padding-left: 14px;
-	-webkit-transition: all .1s ease-in-out;
 	transition: all .1s ease-in-out;
 }
 
@@ -358,7 +354,6 @@
 #adminmenu div.wp-menu-image.svg {
 	background-repeat: no-repeat;
 	background-position: center;
-	-webkit-background-size: 20px auto;
 	background-size: 20px auto;
 }
 
@@ -366,7 +361,6 @@ div.wp-menu-image:before {
 	color: #a0a5aa;
 	color: rgba(240,245,250,0.6);
 	padding: 7px 0;
-	-webkit-transition: all .1s ease-in-out;
 	transition: all .1s ease-in-out;
 }
 
@@ -526,7 +520,6 @@ ul#adminmenu > li.current > a.current:after {
 	font-weight: 600;
 	margin: 1px 0 0 2px;
 	vertical-align: top;
-	-webkit-border-radius: 10px;
 	border-radius: 10px;
 	z-index: 26;
 }
@@ -607,19 +600,16 @@ ul#adminmenu > li.current > a.current:after {
 .folded #collapse-button .collapse-button-icon:after,
 .rtl #collapse-button .collapse-button-icon:after {
 	-webkit-transform: rotate(180deg);
-	-ms-transform: rotate(180deg);
 	transform: rotate(180deg);
 }
 
 .rtl.folded #collapse-button .collapse-button-icon:after {
 	-webkit-transform: none;
-	-ms-transform: none;
 	transform: none;
 }
 
 #collapse-button .collapse-button-icon:after,
 #collapse-button .collapse-button-label {
-	-webkit-transition: all .1s ease-in-out;
 	transition: all .1s ease-in-out;
 }
 
@@ -741,13 +731,11 @@ li#wp-admin-bar-menu-toggle {
 	/* rtl:ignore */
 	.auto-fold #collapse-button .collapse-button-icon:after {
 		-webkit-transform: rotate(180deg);
-		-ms-transform: rotate(180deg);
 		transform: rotate(180deg);
 	}
 
 	.rtl.auto-fold #collapse-button .collapse-button-icon:after {
 		-webkit-transform: none;
-		-ms-transform: none;
 		transform: none;
 	}
 
@@ -828,7 +816,6 @@ li#wp-admin-bar-menu-toggle {
 		display: block;
 		top: 0;
 		left: -1px;
-		-webkit-box-shadow: none;
 		box-shadow: none;
 	}
 
@@ -870,8 +857,6 @@ li#wp-admin-bar-menu-toggle {
 		padding-right: 10px;
 		z-index: 99999;
 		border: none;
-		-webkit-box-sizing: border-box;
-		-moz-box-sizing: border-box;
 		box-sizing: border-box;
 	}
 
@@ -915,8 +900,6 @@ li#wp-admin-bar-menu-toggle {
 		border: none;
 		text-align: center;
 		text-decoration: none;
-		-webkit-box-sizing: border-box;
-		-moz-box-sizing: border-box;
 		box-sizing: border-box;
 	}
 
diff --git a/src/wp-admin/css/color-picker.css b/src/wp-admin/css/color-picker.css
index 30dec299be..d0a41d632d 100644
--- a/src/wp-admin/css/color-picker.css
+++ b/src/wp-admin/css/color-picker.css
@@ -9,7 +9,6 @@
 .wp-color-result {
 	background-color: #f7f7f7;
 	border: 1px solid #ccc;
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
 	cursor: pointer;
 	display: inline-block;
@@ -24,13 +23,11 @@
 	vertical-align: bottom;
 	display: inline-block;
 	padding-left: 30px;
-	-webkit-box-shadow: 0 1px 0 #ccc;
 	box-shadow: 0 1px 0 #ccc;
 }
 
 .wp-color-result:after {
 	background: #f7f7f7;
-	-webkit-border-radius: 0 2px 2px 0;
 	border-radius: 0 2px 2px 0;
 	border-left: 1px solid #ccc;
 	color: #555;
@@ -74,7 +71,6 @@
 
 .wp-color-result:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
@@ -92,7 +88,6 @@
 }
 
 .wp-picker-container .iris-picker {
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	border-color: #ddd;
 	margin-top: 6px;
@@ -127,9 +122,6 @@
 
 .iris-picker .ui-square-handle:focus,
 .iris-picker .iris-strip .ui-slider-handle:focus {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
diff --git a/src/wp-admin/css/common.css b/src/wp-admin/css/common.css
index 44171d060f..9821accd52 100644
--- a/src/wp-admin/css/common.css
+++ b/src/wp-admin/css/common.css
@@ -150,7 +150,6 @@
 	color: #0073aa;
 	z-index: 100000;
 	line-height: normal;
-	-webkit-box-shadow: 0 0 2px 2px rgba(0,0,0,.6);
 	box-shadow: 0 0 2px 2px rgba(0,0,0,.6);
 	text-decoration: none;
 	outline: none;
@@ -184,7 +183,6 @@ p.popular-tags,
 .imgedit-group,
 .comment-ays {
 	border: 1px solid #e5e5e5;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 }
 
@@ -247,11 +245,8 @@ td {
 /* Any change to the default link style must be applied to button-link too. */
 a {
 	color: #0073aa;
-	-webkit-transition-property: border, background, color;
 	transition-property: border, background, color;
-	-webkit-transition-duration: .05s;
 	transition-duration: .05s;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 }
 
@@ -269,9 +264,6 @@ a:focus,
 a:focus .media-icon img,
 .wp-person a:focus .gravatar {
 	color: #124964;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -283,7 +275,6 @@ a:focus .media-icon img,
 
 #adminmenu a:focus,
 .screen-reader-text:focus {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 }
@@ -608,7 +599,6 @@ code {
 	text-decoration: none;
 	border: none;
 	border: 1px solid #ccc;
-	-webkit-border-radius: 2px;
 	border-radius: 2px;
 	background: #f7f7f7;
 	text-shadow: none;
@@ -638,7 +628,6 @@ code {
 
 .wrap .page-title-action:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 2px rgba( 30, 140, 190, 0.8 );
 	box-shadow: 0 0 2px rgba( 30, 140, 190, 0.8 );
 }
 
@@ -656,7 +645,6 @@ code {
 div#widgets-right .widget-top:hover,
 #widgets-left .widget-top:hover {
 	border-color: #999;
-	-webkit-box-shadow: 0 1px 2px rgba(0,0,0,0.1);
 	box-shadow: 0 1px 2px rgba(0,0,0,0.1);
 }
 
@@ -725,7 +713,6 @@ img.emoji {
 	vertical-align: -0.1em !important;
 	background: none !important;
 	padding: 0 !important;
-	-webkit-box-shadow: none !important;
 	box-shadow: none !important;
 }
 
@@ -801,7 +788,6 @@ img.emoji {
 
 .tagchecklist .ntdelbutton .remove-tag-icon:before {
 	margin-left: 2px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	color: #0073aa;
 	/* vertically center the icon cross browsers */
@@ -822,9 +808,6 @@ img.emoji {
 }
 
 .tagchecklist .ntdelbutton:focus .remove-tag-icon:before {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -983,13 +966,10 @@ th.action-links {
 .wp-filter {
 	display: inline-block;
 	position: relative;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	margin: 12px 0 25px;
 	padding: 0 10px;
 	width: 100%;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	border: 1px solid #e5e5e5;
 	background: #fff;
@@ -1013,7 +993,6 @@ th.action-links {
 	position: relative;
 	top: -1px;
 	padding: 4px 10px;
-	-webkit-border-radius: 30px;
 	border-radius: 30px;
 	background: #72777c;
 	color: #fff;
@@ -1053,7 +1032,6 @@ th.action-links {
 }
 
 .filter-links .current {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	border-bottom: 4px solid #666;
 	color: #23282d;
@@ -1098,7 +1076,6 @@ th.action-links {
 	background-color: transparent;
 	color: #666;
 	vertical-align: baseline;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1131,10 +1108,8 @@ th.action-links {
 
 .wp-filter .button.drawer-toggle:active {
 	background: transparent;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	-webkit-transform: none;
-	-ms-transform: none;
 	transform: none;
 }
 
@@ -1162,7 +1137,6 @@ th.action-links {
 }
 
 .show-filters .wp-filter .button.drawer-toggle {
-	-webkit-border-radius: 2px;
 	border-radius: 2px;
 	background: #72777c;
 	color: #fff;
@@ -1178,8 +1152,6 @@ th.action-links {
 }
 
 .filter-group {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	position: relative;
 	float: left;
@@ -1188,7 +1160,6 @@ th.action-links {
 	width: 24%;
 	background: #fff;
 	border: 1px solid #e5e5e5;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 }
 
@@ -1263,7 +1234,6 @@ th.action-links {
 	margin: 0 5px;
 	padding: 4px 8px;
 	border: 1px solid #e5e5e5;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	background: #fff;
 	font-size: 11px;
@@ -1362,7 +1332,6 @@ div.updated,
 div.error {
 	background: #fff;
 	border-left: 4px solid #fff;
-	-webkit-box-shadow: 0 1px 1px 0 rgba( 0, 0, 0, 0.1 );
 	box-shadow: 0 1px 1px 0 rgba( 0, 0, 0, 0.1 );
 	margin: 5px 15px 2px;
 	padding: 1px 12px;
@@ -1390,7 +1359,6 @@ div.error p,
 }
 
 .notice-alt {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1429,7 +1397,6 @@ div.error p,
 
 .notice-dismiss:focus {
 	outline: none;
-	-webkit-box-shadow: 0 0 0 1px #5b9dd9, 0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow: 0 0 0 1px #5b9dd9, 0 0 2px 1px rgba(30, 140, 190, .8);
 }
 
@@ -1543,7 +1510,6 @@ div.error {
 	margin: 25px 20px 0 2px;
 	background-color: #fff;
 	border-left: 4px solid #ffba00;
-	-webkit-box-shadow: 0 1px 1px 0 rgba(0,0,0,0.1);
 	box-shadow: 0 1px 1px 0 rgba(0,0,0,0.1);
 }
 
@@ -1594,11 +1560,8 @@ form.upgrade .hint {
 }
 
 .button.updated-message {
-	-webkit-transition-property: border, background, color;
 	transition-property: border, background, color;
-	-webkit-transition-duration: .05s;
 	transition-duration: .05s;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 }
 
@@ -1654,7 +1617,6 @@ form.upgrade .hint {
 	background-color: #fff;
 	border: 1px solid #ddd;
 	border-top: none;
-	-webkit-box-shadow: 0 1px 0 rgba(0,0,0,.025);
 	box-shadow: 0 1px 0 rgba(0,0,0,.025);
 }
 
@@ -1666,7 +1628,6 @@ form.upgrade .hint {
 	border: 1px solid #ddd;
 	border-top: none;
 	background: #fff;
-	-webkit-box-shadow: 0 1px 1px -1px rgba(0,0,0,0.1);
 	box-shadow: 0 1px 1px -1px rgba(0,0,0,0.1);
 }
 
@@ -1678,7 +1639,6 @@ form.upgrade .hint {
 #screen-meta-links .show-settings {
 	border: 0;
 	background: none;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	color: #72777c;
 	line-height: 1.7;
@@ -1692,10 +1652,8 @@ form.upgrade .hint {
 }
 
 #screen-meta-links .show-settings:active {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	-webkit-transform: none;
-	-ms-transform: none;
 	transform: none;
 }
 
@@ -1829,7 +1787,6 @@ form.upgrade .hint {
 #contextual-help-wrap.no-sidebar #contextual-help-back {
 	right: 0;
 	border-right-width: 0;
-	-webkit-border-bottom-right-radius: 2px;
 	border-bottom-right-radius: 2px;
 }
 
@@ -1870,7 +1827,6 @@ form.upgrade .hint {
 	margin: 0 -1px 0 0;
 	border-left: 2px solid #00a0d2;
 	background: #f6fbfd;
-	-webkit-box-shadow: 0 2px 0 rgba(0,0,0,0.02), 0 1px 0 rgba(0,0,0,0.02);
 	box-shadow: 0 2px 0 rgba(0,0,0,0.02), 0 1px 0 rgba(0,0,0,0.02);
 }
 
@@ -1912,8 +1868,6 @@ form.upgrade .hint {
 
 html.wp-toolbar {
 	padding-top: 32px;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -1960,8 +1914,6 @@ html.wp-toolbar {
 }
 
 .postbox-container .meta-box-sortables {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -2091,7 +2043,6 @@ html.wp-toolbar {
 
 .postbox.closed h3 {
 	border: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -2100,7 +2051,6 @@ html.wp-toolbar {
 }
 
 .postbox table.widefat {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -2186,7 +2136,6 @@ h3 .nav-tab, /* Back-compat for pre-4.4 */
 
 .nav-tab-active,
 .nav-tab:focus:active {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -2234,7 +2183,6 @@ h1.nav-tab-wrapper, /* Back-compat for pre-4.4 */
 
 .spinner {
 	background: url(../images/spinner.gif) no-repeat;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 	display: inline-block;
 	visibility: hidden;
@@ -2470,7 +2418,6 @@ div.star-holder .star-rating {
 	font-weight: 400;
 	font-style: normal;
 	vertical-align: top;
-	-webkit-transition: color .1s ease-in 0;
 	transition: color .1s ease-in 0;
 	text-align: center;
 	color: #ffb900;
@@ -2486,7 +2433,6 @@ div.star-holder .star-rating {
 
 .rtl .star-rating .star-half {
 	-webkit-transform: rotateY(180deg);
-	-ms-transform: rotateY(180deg);
 	transform: rotateY(180deg);
 }
 
@@ -2530,7 +2476,6 @@ div.action-links {
 #plugin-information-title.with-banner {
 	margin-right: 0;
 	height: 250px;
-	-webkit-background-size: cover;
 	background-size: cover;
 }
 
@@ -2550,8 +2495,6 @@ div.action-links {
 	display: inline-block;
 	font-size: 30px;
 	line-height: 50px;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	max-width: 100%;
 	padding: 0 15px;
@@ -2559,9 +2502,7 @@ div.action-links {
 	color: #fff;
 	background: rgba( 30, 30, 30, 0.9 );
 	text-shadow: 0 1px 3px rgba( 0, 0, 0, 0.4 );
-	-webkit-box-shadow: 0 0 30px rgba( 255, 255, 255, 0.1 );
 	box-shadow: 0 0 30px rgba( 255, 255, 255, 0.1 );
-	-webkit-border-radius: 8px;
 	border-radius: 8px;
 }
 
@@ -2577,7 +2518,6 @@ div.action-links {
 	height: 250px;
 	width: 100%;
 	background: transparent;
-	-webkit-box-shadow: inset 0 0 50px 4px rgba( 0, 0, 0, 0.2 ), inset 0 -1px 0 rgba( 0, 0, 0, 0.1 );
 	box-shadow: inset 0 0 50px 4px rgba( 0, 0, 0, 0.2 ), inset 0 -1px 0 rgba( 0, 0, 0, 0.1 );
 }
 
@@ -2602,7 +2542,6 @@ div.action-links {
 	line-height: 18px;
 	font-size: 14px;
 	text-decoration: none;
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -2634,13 +2573,11 @@ div.action-links {
 	left: 0;
 	min-height: 100%;
 	/* Height of title + tabs + install now */
-	min-height: -webkit-calc( 100% - 152px );
 	min-height: calc( 100% - 152px );
 }
 
 #plugin-information-content.with-banner {
 	/* Height of banner + tabs + install now */
-	min-height: -webkit-calc( 100% - 346px );
 	min-height: calc( 100% - 346px );
 }
 
@@ -2794,7 +2731,6 @@ div.action-links {
 	max-width: 100%;
 	width: auto;
 	height: auto;
-	-webkit-box-shadow: 0 1px 2px rgba( 0, 0, 0, 0.3 );
 	box-shadow: 0 1px 2px rgba( 0, 0, 0, 0.3 );
 }
 
@@ -2965,7 +2901,6 @@ body.index-php #TB_window.thickbox-loading:before {
 	z-index: -1;
 	margin: -10px 0 0 -10px;
 	background: #fcfcfc url(../images/spinner.gif) no-repeat center;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 	-webkit-transform: translateZ(0);
 	transform: translateZ(0);
@@ -3031,7 +2966,6 @@ body.index-php #TB_closeWindowButton:hover,
 body.index-php #TB_closeWindowButton:focus {
 	color: #00a0d2;
 	outline: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -3111,7 +3045,6 @@ img {
 .js .postbox .handlediv .toggle-indicator:before {
 	margin-top: 4px;
 	width: 20px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	text-indent: -1px; /* account for the dashicon alignment */
 }
@@ -3127,15 +3060,11 @@ img {
 }
 
 .js .postbox .handlediv:focus {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 }
 
 .js .postbox .handlediv:focus .toggle-indicator:before {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -3250,7 +3179,6 @@ img {
 
 .widget-top .widget-action .toggle-indicator:before {
 	padding: 1px 2px 1px 0px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 }
 
@@ -3280,9 +3208,6 @@ img {
 }
 
 .widget-top .widget-action:focus .toggle-indicator:before {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30,140,190,.8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30,140,190,.8);
@@ -3312,7 +3237,6 @@ img {
  */
 .ui-draggable-handle,
 .ui-sortable-handle {
-	-ms-touch-action: none;
 	touch-action: none;
 }
 
@@ -3566,7 +3490,6 @@ img {
 	div.star-holder,
 	div.star-holder .star-rating {
 		background: url(../images/stars-2x.png?ver=20121108) repeat-x bottom left;
-		-webkit-background-size: 21px 37px;
 		background-size: 21px 37px;
 	}
 
diff --git a/src/wp-admin/css/customize-controls.css b/src/wp-admin/css/customize-controls.css
index 90c69c6910..998ee632f0 100644
--- a/src/wp-admin/css/customize-controls.css
+++ b/src/wp-admin/css/customize-controls.css
@@ -62,7 +62,6 @@ body {
 	position: absolute;
 	z-index: 9;
 	width: 100%;
-	-webkit-box-shadow: 0 1px 0 rgba(0, 0, 0, .1);
 	box-shadow: 0 1px 0 rgba(0, 0, 0, .1);
 }
 
@@ -130,7 +129,6 @@ body {
 	width: 20px;
 	height: 20px;
 	cursor: pointer;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	-webkit-appearance: none;
 	background: transparent;
@@ -200,9 +198,6 @@ body {
 	background-color: #fff;
 	border-bottom: 1px solid #ddd;
 	border-left: 4px solid #fff;
-	-webkit-transition: .15s color ease-in-out,
-	            .15s background-color ease-in-out,
-	            .15s border-color ease-in-out;
 	transition: .15s color ease-in-out,
 	            .15s background-color ease-in-out,
 	            .15s border-color ease-in-out;
@@ -280,8 +275,6 @@ body {
 	width: 100%;
 	margin: 0;
 	padding: 12px;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -292,19 +285,13 @@ body {
 	width: 100%;
 	margin: 0;
 	padding: 0;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
-	-webkit-transition: 0.18s -webkit-transform cubic-bezier(0.645, 0.045, 0.355, 1);
 	transition: 0.18s -webkit-transform cubic-bezier(0.645, 0.045, 0.355, 1);
-	-webkit-transition: 0.18s transform cubic-bezier(0.645, 0.045, 0.355, 1);
 	transition: 0.18s transform cubic-bezier(0.645, 0.045, 0.355, 1);
-	-webkit-transition: 0.18s transform cubic-bezier(0.645, 0.045, 0.355, 1), 0.18s -webkit-transform cubic-bezier(0.645, 0.045, 0.355, 1);
 	transition: 0.18s transform cubic-bezier(0.645, 0.045, 0.355, 1), 0.18s -webkit-transform cubic-bezier(0.645, 0.045, 0.355, 1); /* easeInOutCubic */
 }
 
 #customize-theme-controls .customize-pane-child.skip-transition {
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -316,7 +303,6 @@ body {
 	max-height: none;
 	overflow: auto;
 	-webkit-transform: none;
-	-ms-transform: none;
 	transform: none;
 }
 
@@ -329,7 +315,6 @@ body {
 	max-height: none;
 	overflow: hidden;
 	-webkit-transform: translateX(100%);
-	-ms-transform: translateX(100%);
 	transform: translateX(100%);
 }
 
@@ -337,7 +322,6 @@ body {
 #customize-theme-controls .customize-pane-child.current-panel,
 #customize-theme-controls .customize-themes-panel.customize-pane-child.current-panel {
 	-webkit-transform: none;
-	-ms-transform: none;
 	transform: none;
 }
 
@@ -353,7 +337,6 @@ body {
 	height: 0;
 	overflow: hidden;
 	-webkit-transform: translateX(-100%);
-	-ms-transform: translateX(-100%);
 	transform: translateX(-100%);
 }
 
@@ -375,7 +358,6 @@ body {
 .in-themes-panel #customize-theme-controls .customize-pane-parent,
 .in-themes-panel #customize-info {
 	-webkit-transform: translateX(100%);
-	-ms-transform: translateX(100%);
 	transform: translateX(100%);
 }
 
@@ -466,14 +448,9 @@ h3.customize-section-title {
 	color: #444;
 	text-align: left;
 	cursor: pointer;
-	-webkit-transition: color .15s ease-in-out,
-	            border-color .15s ease-in-out,
-	            background .15s ease-in-out;
 	transition: color .15s ease-in-out,
 	            border-color .15s ease-in-out,
 	            background .15s ease-in-out;
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
 }
 
@@ -489,12 +466,8 @@ h3.customize-section-title {
 	border: none;
 	border-right: 1px solid #ddd;
 	border-left: 4px solid #fff;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	cursor: pointer;
-	-webkit-transition: color .15s ease-in-out,
-	            border-color .15s ease-in-out,
-	            background .15s ease-in-out;
 	transition: color .15s ease-in-out,
 	            border-color .15s ease-in-out,
 	            background .15s ease-in-out;
@@ -532,7 +505,6 @@ h3.customize-section-title {
 	color: #0073aa;
 	border-top-color: #0073aa;
 	outline: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -545,7 +517,6 @@ h3.customize-section-title {
 	background: #f3f3f5;
 	border-left-color: #0073aa;
 	outline: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -567,7 +538,6 @@ h3.customize-section-title {
 
 .wp-full-overlay-sidebar .wp-full-overlay-header {
 	background-color: #eee;
-	-webkit-transition: padding ease-in-out .18s;
 	transition: padding ease-in-out .18s;
 }
 
@@ -735,7 +705,6 @@ p.customize-section-description {
 
 #available-menu-items .accordion-section-content .new-content-item,
 .customize-control-dropdown-pages .new-content-item {
-	width: -webkit-calc(100% - 30px);
 	width: calc(100% - 30px);
 	padding: 8px 15px;
 	position: absolute;
@@ -743,9 +712,6 @@ p.customize-section-description {
 	z-index: 10;
 	background: #eee;
 	display: -webkit-box;
-	display: -moz-box;
-	display: -ms-flexbox;
-	display: -webkit-flex;
 	display: flex;
 }
 
@@ -758,10 +724,6 @@ p.customize-section-description {
 #available-menu-items .new-content-item .create-item-input,
 .customize-control-dropdown-pages .new-content-item .create-item-input {
 	-webkit-box-flex: 10;
-	-webkit-flex-grow: 10;
-	-moz-box-flex: 10;
-	-ms-flex-positive: 10;
-	-ms-flex: 10;
 	flex-grow: 10;
 }
 
@@ -769,10 +731,6 @@ p.customize-section-description {
 .customize-control-dropdown-pages .new-content-item .add-content {
 	margin: 2px 0 2px 6px;
 	-webkit-box-flex: 10;
-	-webkit-flex-grow: 10;
-	-moz-box-flex: 10;
-	-ms-flex-positive: 10;
-	-ms-flex: 10;
 	flex-grow: 1;
 }
 
@@ -814,9 +772,7 @@ p.customize-section-description {
 
 #customize-controls .customize-control-widget_form.has-error .widget .widget-top,
 .customize-control-nav_menu_item.has-error .menu-item-bar .menu-item-handle {
-	-webkit-box-shadow: inset 0 0 0 2px #dc3232;
 	box-shadow: inset 0 0 0 2px #dc3232;
-	-webkit-transition: .15s box-shadow linear;
 	transition: .15s box-shadow linear;
 }
 
@@ -986,8 +942,6 @@ p.customize-section-description {
 	text-align: center;
 	cursor: default;
 	border: 1px dashed #b4b9be;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	padding: 9px 0;
 	line-height: 20px;
@@ -1039,7 +993,6 @@ p.customize-section-description {
 	height: auto;
 	top: 0; left: 0; bottom: 0; right: 0;
 	border: 4px solid #00a0d2;
-	-webkit-border-radius: 2px;
 	border-radius: 2px;
 }
 
@@ -1077,7 +1030,6 @@ p.customize-section-description {
 
 .customize-control-header .random.placeholder {
 	cursor: pointer;
-	-webkit-border-radius: 2px;
 	border-radius: 2px;
 	height: 40px;
 }
@@ -1121,9 +1073,6 @@ p.customize-section-description {
 
 .customize-control-header .choice:focus {
 	outline: none;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 3px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 3px 1px rgba(30, 140, 190, .8);
@@ -1178,14 +1127,12 @@ p.customize-section-description {
 .customize-section-description-container + #customize-control-custom_css:last-child textarea {
 	border-right: 0;
 	border-left: 0;
-	height: -webkit-calc( 100vh - 185px );
 	height: calc( 100vh - 185px );
 	resize: none;
 }
 .customize-section-description-container + #customize-control-custom_css:last-child {
 	margin-left: -12px;
 	width: 299px;
-	width: -webkit-calc( 100% + 24px );
 	width: calc( 100% + 24px );
 	margin-bottom: -12px;
 }
@@ -1195,7 +1142,6 @@ p.customize-section-description {
 		margin-right: 0;
 	}
 	.customize-section-description-container + #customize-control-custom_css:last-child textarea {
-		height: -webkit-calc( 100vh - 140px );
 		height: calc( 100vh - 140px );
 	}
 }
@@ -1275,8 +1221,6 @@ p.customize-section-description {
 #customize-controls .customize-themes-panel {
 	padding: 0 8px;
 	background: #f1f1f1;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -1405,7 +1349,6 @@ body.cheatin {
 	padding: 1em 2em;
 	max-width: 700px;
 	min-width: 0;
-	-webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.13);
 	box-shadow: 0 1px 3px rgba(0,0,0,0.13);
 }
 
@@ -1436,7 +1379,6 @@ body.cheatin p {
 	cursor: pointer;
 	float: right;
 	margin-left: 10px;
-	-webkit-transition: all 0.2s;
 	transition: all 0.2s;
 	-webkit-user-select: none;
 	-moz-user-select: none;
@@ -1462,7 +1404,6 @@ body.cheatin p {
 	top: -1px;
 	font: normal 20px/1 dashicons;
 	vertical-align: middle;
-	-webkit-transition: all 0.2s;
 	transition: all 0.2s;
 	-webkit-font-smoothing: antialiased;
 	-moz-osx-font-smoothing: grayscale;
@@ -1507,7 +1448,6 @@ body.cheatin p {
 	height: 40px;
 	background: transparent;
 	border: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1574,7 +1514,6 @@ body.adding-widget .add-new-widget:hover,
 	background: #eee;
 	border-color: #929793;
 	color: #32373c;
-	-webkit-box-shadow: inset 0 2px 5px -3px rgba(0, 0, 0, 0.5);
 	box-shadow: inset 0 2px 5px -3px rgba(0, 0, 0, 0.5);
 }
 
@@ -1582,7 +1521,6 @@ body.adding-widget .add-new-widget:before,
 .adding-menu-items .add-new-menu-item:before,
 #accordion-section-add_menu .add-new-menu-item.open:before {
 	-webkit-transform: rotate(45deg);
-	-ms-transform: rotate(45deg);
 	transform: rotate(45deg);
 }
 
@@ -1599,7 +1537,6 @@ body.adding-widget .add-new-widget:before,
 	margin: 0;
 	z-index: 4;
 	background: #eee;
-	-webkit-transition: left .18s;
 	transition: left .18s;
 	border-right: 1px solid #ddd;
 }
@@ -1634,8 +1571,6 @@ body.adding-widget .add-new-widget:before,
 #available-widgets-filter,
 #available-menu-items-search .accordion-section-title {
 	padding: 13px 15px;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -1710,9 +1645,6 @@ body.adding-widget .add-new-widget:before,
 
 #available-widgets-filter .clear-results:focus,
 #available-menu-items-search .clear-results:focus {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -1744,7 +1676,6 @@ body.adding-widget .add-new-widget:before,
 #available-menu-items .item-top:hover {
 	border: none;
 	background: transparent;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1755,9 +1686,6 @@ body.adding-widget .add-new-widget:before,
 	background: #fff;
 	border-bottom: 1px solid #ddd;
 	border-left: 4px solid #fff;
-	-webkit-transition: .15s color ease-in-out,
-	            .15s background-color ease-in-out,
-	            .15s border-color ease-in-out;
 	transition: .15s color ease-in-out,
 	            .15s background-color ease-in-out,
 	            .15s border-color ease-in-out;
@@ -1838,7 +1766,6 @@ body.adding-widget .add-new-widget:before,
 		border-right: 1px solid #ddd;
 		color: #555d66;
 		cursor: pointer;
-		-webkit-transition: color .1s ease-in-out, background .1s ease-in-out;
 		transition: color .1s ease-in-out, background .1s ease-in-out;
 	}
 
diff --git a/src/wp-admin/css/customize-nav-menus.css b/src/wp-admin/css/customize-nav-menus.css
index f2186fbb2f..f9d8f81703 100644
--- a/src/wp-admin/css/customize-nav-menus.css
+++ b/src/wp-admin/css/customize-nav-menus.css
@@ -30,8 +30,6 @@
 .wp-customizer .menu-item-bar .menu-item-handle,
 .wp-customizer .menu-item-settings,
 .wp-customizer .menu-item-settings .description-thin {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -145,7 +143,6 @@
 	width: 30px;
 	height: 38px;
 	margin-right: 0 !important;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 	overflow: hidden;
@@ -249,7 +246,6 @@
 
 .customize-screen-options-toggle:focus:before,
 #customize-controls .customize-info .customize-help-toggle:focus:before {
-	-webkit-border-radius: 100%;
 	border-radius: 100%;
 }
 
@@ -283,7 +279,6 @@
 	display: block;
 	padding: 1px 2px 1px 0px;
 	speak: none;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	color: #72777c;
 	font: normal 20px/1 dashicons;
@@ -388,7 +383,6 @@
 .control-section-nav_menu.menu .sortable-placeholder {
 	margin-top: 0;
 	margin-bottom: 1px;
-	max-width: -webkit-calc(100% - 2px);
 	max-width: calc(100% - 2px);
 	float: left;
 	display: list-item;
@@ -432,7 +426,6 @@
 	position: absolute;
 	top: 9px;
 	left: 5px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	font: normal 20px/1 dashicons;
 	-webkit-font-smoothing: antialiased;
@@ -445,7 +438,6 @@
 
 .menu-item-bar .item-delete:hover,
 .menu-item-bar .item-delete:focus {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 	color: #f00;
@@ -476,7 +468,6 @@
 	border-left: none;
 	border-right: none;
 	background: #fff;
-	-webkit-transition: background-color 0.15s;
 	transition: background-color 0.15s;
 	/* Reset the value inherited from the base .accordion-section-title style. Ticket #37589. */
 	-webkit-user-select: auto;
@@ -519,7 +510,6 @@
 	position: absolute;
 	top: 5px;
 	right: 5px;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 	cursor: pointer;
@@ -590,7 +580,6 @@
 }
 
 #available-menu-items .menu-item-handle {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	margin-top: -1px;
 }
@@ -611,7 +600,6 @@
 	color: #82878c;
 	width: 30px;
 	height: 38px;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 	cursor: pointer;
@@ -629,7 +617,6 @@
 	top: 3px;
 	display: inline-block;
 	height: 20px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	font: normal 20px/1.05 dashicons; /* line height is to account for the dashicon's vertical alignment */
 }
@@ -667,8 +654,6 @@
 	max-height: none;
 	width: 100%;
 	padding: 1px 15px 15px;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -695,7 +680,6 @@
 }
 
 #customize-preview {
-	-webkit-transition: all 0.2s;
 	transition: all 0.2s;
 }
 
@@ -740,11 +724,8 @@ body.adding-menu-items #customize-preview iframe {
 }
 
 .added-menu-item .menu-item-handle {
-	-webkit-transition-property: opacity, background, color;
 	transition-property: opacity, background, color;
-	-webkit-transition-duration: 1.25s;
 	transition-duration: 1.25s;
-	-webkit-transition-timing-function: cubic-bezier( .25, -2.5, .75, 8 );
 	transition-timing-function: cubic-bezier( .25, -2.5, .75, 8 ); /* Replacement for .hide().fadeIn('slow') in JS to add emphasis when it's loaded. */
 }
 
@@ -842,9 +823,6 @@ li.assigned-to-menu-location .add-new-menu-item {
 .menu-delete:focus,
 .menu-item-bar .item-delete:focus:before,
 #available-menu-items .item-add:focus:before {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
diff --git a/src/wp-admin/css/customize-widgets.css b/src/wp-admin/css/customize-widgets.css
index 0a9fbf5869..ab4f91b0e1 100644
--- a/src/wp-admin/css/customize-widgets.css
+++ b/src/wp-admin/css/customize-widgets.css
@@ -21,7 +21,6 @@
 /* Note: widget-tops are more compact when (max-height: 700px) and (min-width: 981px). */
 .customize-control-widget_form .widget-top {
 	background: #fff;
-	-webkit-transition: opacity 0.5s;
 	transition: opacity 0.5s;
 }
 
@@ -76,7 +75,6 @@
 }
 
 .customize-control-widget_form.wide-widget-control .widget-top {
-	-webkit-transition: background-color 0.4s;
 	transition: background-color 0.4s;
 }
 .customize-control-widget_form.wide-widget-control.expanding .widget-top,
@@ -114,7 +112,6 @@
 .control-section.accordion-section.highlighted > .accordion-section-title,
 .customize-control-widget_form.highlighted {
 	outline: none;
-	-webkit-box-shadow: 0 0 2px rgba(30,140,190,0.8);
 	box-shadow: 0 0 2px rgba(30,140,190,0.8);
 	position: relative;
 	z-index: 1;
@@ -239,7 +236,6 @@
 }
 
 .ios #available-widgets {
-	-webkit-transition: left 0s;
 	transition: left 0s;
 }
 
@@ -266,7 +262,6 @@
 }
 
 #customize-preview {
-	-webkit-transition: all 0.2s;
 	transition: all 0.2s;
 }
 
@@ -305,8 +300,6 @@ body.adding-widget #customize-preview {
 	color: #32373c;
 	font: normal 20px/1 dashicons;
 	text-align: center;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	-webkit-font-smoothing: antialiased;
 	-moz-osx-font-smoothing: grayscale;
@@ -445,7 +438,6 @@ body.adding-widget #customize-preview {
 	}
 
 	.widget-top {
-		-webkit-box-shadow: none;
 		box-shadow: none;
 		margin-top: -1px;
 	}
diff --git a/src/wp-admin/css/dashboard.css b/src/wp-admin/css/dashboard.css
index c13567870a..f64cc92422 100644
--- a/src/wp-admin/css/dashboard.css
+++ b/src/wp-admin/css/dashboard.css
@@ -104,7 +104,6 @@
 	margin: 16px 0;
 	padding: 23px 10px 0;
 	border: 1px solid #e5e5e5;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	background: #fff;
 	font-size: 13px;
@@ -154,7 +153,6 @@
 	position: absolute;
 	top: 8px;
 	left: 0;
-	-webkit-transition: all .1s ease-in-out;
 	transition: all .1s ease-in-out;
 }
 
@@ -617,8 +615,6 @@ form.initial-form.quickpress-open input#title {
 
 #dashboard_quick_press input,
 #dashboard_quick_press textarea {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	margin: 0;
 }
@@ -952,7 +948,6 @@ form.initial-form.quickpress-open input#title {
 
 #activity-widget #the-comment-list .comment,
 #activity-widget #the-comment-list .pingback {
-	-webkit-box-shadow: inset 0 1px 0 rgba(0, 0, 0, 0.06);
 	box-shadow: inset 0 1px 0 rgba(0, 0, 0, 0.06);
 }
 
@@ -1085,7 +1080,6 @@ a.rsswidget {
 	background-image: none;
 	border-color: #edc048;
 	color: #fff;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1098,7 +1092,6 @@ a.rsswidget {
 	border-bottom-color: #f6e2ac;
 	background: transparent none;
 	color: #fff;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
diff --git a/src/wp-admin/css/deprecated-media.css b/src/wp-admin/css/deprecated-media.css
index 9249309cd2..01848f35c8 100644
--- a/src/wp-admin/css/deprecated-media.css
+++ b/src/wp-admin/css/deprecated-media.css
@@ -31,7 +31,6 @@ div#media-upload-header {
 	border-bottom: 1px solid #ddd;
 	background-color: #f9f9f9;
 	text-decoration: none;
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -394,25 +393,21 @@ table.not-image tr.image-only {
 
 	.image-align-none-label {
 		background-image: url(../images/align-none-2x.png?ver=20120916);
-		-webkit-background-size: 21px 15px;
 		background-size: 21px 15px;
 	}
 
 	.image-align-left-label {
 		background-image: url(../images/align-left-2x.png?ver=20120916);
-		-webkit-background-size: 22px 15px;
 		background-size: 22px 15px;
 	}
 
 	.image-align-center-label {
 		background-image: url(../images/align-center-2x.png?ver=20120916);
-		-webkit-background-size: 21px 15px;
 		background-size: 21px 15px;
 	}
 
 	.image-align-right-label {
 		background-image: url(../images/align-right-2x.png?ver=20120916);
-		-webkit-background-size: 22px 15px;
 		background-size: 22px 15px;
 	}
 }
diff --git a/src/wp-admin/css/edit.css b/src/wp-admin/css/edit.css
index 03ace83e6a..64b98ae99f 100644
--- a/src/wp-admin/css/edit.css
+++ b/src/wp-admin/css/edit.css
@@ -154,7 +154,6 @@ body.post-new-php .submitbox .submitdelete {
 	position: relative;
 	min-width: 255px;
 	border: 1px solid #e5e5e5;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	background: #fff;
 }
@@ -279,10 +278,8 @@ ul.wp-tab-bar li {
 	height: auto;
 	width: auto;
 	vertical-align: top;
-	background-image: -webkit-linear-gradient(45deg, #c4c4c4 25%, transparent 25%, transparent 75%, #c4c4c4 75%, #c4c4c4), -webkit-linear-gradient(45deg, #c4c4c4 25%, transparent 25%, transparent 75%, #c4c4c4 75%, #c4c4c4);
 	background-image: linear-gradient(45deg, #c4c4c4 25%, transparent 25%, transparent 75%, #c4c4c4 75%, #c4c4c4), linear-gradient(45deg, #c4c4c4 25%, transparent 25%, transparent 75%, #c4c4c4 75%, #c4c4c4);
 	background-position: 0 0, 10px 10px;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 }
 
@@ -315,7 +312,6 @@ form#tags-filter {
 	border: 1px solid #e5e5e5;
 	border-top: none;
 	background-color: #f7f7f7;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	z-index: 999;
 }
@@ -368,7 +364,6 @@ form#tags-filter {
 }
 
 .wp-editor-expand #wp-content-editor-container {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	margin-top: -1px;
 }
@@ -511,7 +506,6 @@ span.wp-media-buttons-icon:before {
 	width: 450px;
 	margin-left: -225px;
 	background: #fff;
-	-webkit-box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	line-height: 1.5;
 	z-index: 1000005;
@@ -795,7 +789,6 @@ span.wp-media-buttons-icon:before {
 .post-state-format:before,
 .post-format-icon:before {
 	color: #ddd;
-	-webkit-transition: all .1s ease-in-out;
 	transition: all .1s ease-in-out;
 }
 
@@ -1230,11 +1223,8 @@ table.links-table {
 .focus-on #screen-meta-links,
 .focus-on #screen-meta {
 	opacity: 0;
-	-webkit-transition-duration: 0.6s;
 	transition-duration: 0.6s;
-	-webkit-transition-property: opacity;
 	transition-property: opacity;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 }
 
@@ -1254,11 +1244,8 @@ table.links-table {
 .focus-off #screen-meta-links,
 .focus-off #screen-meta {
 	opacity: 1;
-	-webkit-transition-duration: 0.2s;
 	transition-duration: 0.2s;
-	-webkit-transition-property: opacity;
 	transition-property: opacity;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 }
 
@@ -1268,35 +1255,27 @@ table.links-table {
 
 .focus-on #adminmenuback,
 .focus-on #adminmenuwrap {
-	-webkit-transition-duration: 0.6s;
 	transition-duration: 0.6s;
-	-webkit-transition-property: -webkit-transform;
 	transition-property: -webkit-transform;
 	transition-property: transform;
 	transition-property: transform, -webkit-transform;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 }
 
 .focus-on #adminmenuback,
 .focus-on #adminmenuwrap {
 	-webkit-transform: translateX( -100% );
-	-ms-transform: translateX( -100% );
 	transform: translateX( -100% );
 }
 
 .focus-off #adminmenuback,
 .focus-off #adminmenuwrap {
 	-webkit-transform: translateX( 0 );
-	-ms-transform: translateX( 0 );
 	transform: translateX( 0 );
-	-webkit-transition-duration: 0.2s;
 	transition-duration: 0.2s;
-	-webkit-transition-property: -webkit-transform;
 	transition-property: -webkit-transform;
 	transition-property: transform;
 	transition-property: transform, -webkit-transform;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 }
 
@@ -1312,7 +1291,6 @@ table.links-table {
 	#content-resize-handle,
 	#post-body .wp_themeSkin .mceStatusbar a.mceResize {
 		background: transparent url(../images/resize-2x.gif) no-repeat scroll right bottom;
-		-webkit-background-size: 11px 11px;
 		background-size: 11px 11px;
 	}
 
diff --git a/src/wp-admin/css/forms.css b/src/wp-admin/css/forms.css
index b46cb5f3b4..50861ae4cb 100644
--- a/src/wp-admin/css/forms.css
+++ b/src/wp-admin/css/forms.css
@@ -1,8 +1,6 @@
 /* Include margin and padding in the width calculation of input and textarea. */
 input,
 textarea {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -26,12 +24,10 @@ input[type="week"],
 select,
 textarea {
 	border: 1px solid #ddd;
-	-webkit-box-shadow: inset 0 1px 2px rgba( 0, 0, 0, 0.07 );
 	box-shadow: inset 0 1px 2px rgba( 0, 0, 0, 0.07 );
 	background-color: #fff;
 	color: #32373c;
 	outline: none;
-	-webkit-transition: 0.05s border-color ease-in-out;
 	transition: 0.05s border-color ease-in-out;
 }
 
@@ -55,7 +51,6 @@ input[type="radio"]:focus,
 select:focus,
 textarea:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 2px rgba( 30, 140, 190, 0.8 );
 	box-shadow: 0 0 2px rgba( 30, 140, 190, 0.8 );
 }
 
@@ -89,9 +84,7 @@ input[type="radio"] {
 	width: 16px;
 	min-width: 16px;
 	-webkit-appearance: none;
-	-webkit-box-shadow: inset 0 1px 2px rgba( 0, 0, 0, 0.1 );
 	box-shadow: inset 0 1px 2px rgba( 0, 0, 0, 0.1 );
-	-webkit-transition: .05s border-color ease-in-out;
 	transition: .05s border-color ease-in-out;
 }
 
@@ -119,7 +112,6 @@ td > input[type="checkbox"],
 }
 
 input[type="radio"] {
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	margin-right: 4px;
 	line-height: 10px;
@@ -146,7 +138,6 @@ input[type="checkbox"]:checked:before {
 input[type="radio"]:checked:before {
 	content: "\2022";
 	text-indent: -9999px;
-	-webkit-border-radius: 50px;
 	border-radius: 50px;
 	font-size: 24px;
 	width: 6px;
@@ -191,7 +182,6 @@ input,
 select {
 	font-size: 14px;
 	padding: 3px 5px;
-	-webkit-border-radius: 0;
 	border-radius: 0; /* Reset mobile webkit's default element styling */
 }
 
@@ -249,8 +239,7 @@ textarea[readonly] {
 .form-invalid input, .form-invalid input:focus,
 .form-invalid select, .form-invalid select:focus {
 	border-color: #dc3232 !important;
-	-webkit-box-shadow: 0 0 2px rgba( 204, 0, 0, 0.8 );
- 	box-shadow: 0 0 2px rgba( 204, 0, 0, 0.8 );
+ box-shadow: 0 0 2px rgba( 204, 0, 0, 0.8 );
 }
 
 .form-table .form-required.form-invalid td:after {
@@ -286,7 +275,6 @@ textarea:disabled,
 textarea.disabled {
 	background: rgba( 255, 255, 255, 0.5 );
 	border-color: rgba( 222, 222, 222, 0.75 );
-	-webkit-box-shadow: inset 0 1px 2px rgba( 0, 0, 0, 0.04 );
 	box-shadow: inset 0 1px 2px rgba( 0, 0, 0, 0.04 );
 	color: rgba( 51, 51, 51, 0.5 );
 }
@@ -296,7 +284,6 @@ input[type="file"].disabled,
 input[type="range"]:disabled,
 input[type="range"].disabled {
 	background: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	cursor: default;
 }
@@ -340,9 +327,7 @@ input[type="radio"].disabled:checked:before {
 .submit {
 	padding: 1.5em 0;
 	margin: 5px 0;
-	-webkit-border-bottom-left-radius: 3px;
 	border-bottom-left-radius: 3px;
-	-webkit-border-bottom-right-radius: 3px;
 	border-bottom-right-radius: 3px;
 	border: none;
 }
@@ -466,8 +451,6 @@ fieldset label,
 	padding: 3px 5px;
 	text-align: center;
 	width: 25em;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	opacity: 0;
 }
@@ -584,7 +567,6 @@ ul#add-to-blog-users {
 	position: absolute;
 	z-index: 10000;
 	border: 1px solid #5b9dd9;
-	-webkit-box-shadow: 0 1px 2px rgba( 30, 140, 190, 0.8 );
 	box-shadow: 0 1px 2px rgba( 30, 140, 190, 0.8 );
 	background-color: #fff;
 }
@@ -732,8 +714,6 @@ table.form-table td .updated p {
 	display: inline-block;
 	width: 24%;
 	padding: 5px 15px 15px;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	margin-bottom: 3px;
 }
@@ -790,7 +770,6 @@ table.form-table td .updated p {
 	min-width: 255px;
 	max-width: 520px;
 	border: 1px solid #e5e5e5;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	background: #fff;
 }
@@ -826,7 +805,6 @@ table.form-table td .updated p {
 	cursor: move;
 	color: #32373c;
 	background: #e5e5e5;
-	-webkit-border-radius: 5px;
 	border-radius: 5px;
 	border: 1px solid #b4b9be;
 	font-style: normal;
@@ -849,17 +827,13 @@ table.form-table td .updated p {
 	bottom: 9px;
 	background: transparent;
 	-webkit-transform: skew(20deg) rotate(6deg);
-	-ms-transform: skew(20deg) rotate(6deg);
 	transform: skew(20deg) rotate(6deg);
-	-webkit-box-shadow: 0 10px 8px rgba(0, 0, 0, 0.6);
 	box-shadow: 0 10px 8px rgba(0, 0, 0, 0.6);
 }
 
 .pressthis-bookmarklet:hover:after {
 	-webkit-transform: skew(20deg) rotate(9deg);
-	-ms-transform: skew(20deg) rotate(9deg);
 	transform: skew(20deg) rotate(9deg);
-	-webkit-box-shadow: 0 10px 8px rgba(0, 0, 0, 0.7);
 	box-shadow: 0 10px 8px rgba(0, 0, 0, 0.7);
 }
 
@@ -1176,8 +1150,6 @@ table.form-table td .updated p {
 	}
 
 	.form-table {
-		-webkit-box-sizing: border-box;
-		-moz-box-sizing: border-box;
 		box-sizing: border-box;
 	}
 
@@ -1224,8 +1196,6 @@ table.form-table td .updated p {
 		padding: 7px 10px;
 		display: block;
 		max-width: none;
-		-webkit-box-sizing: border-box;
-		-moz-box-sizing: border-box;
 		box-sizing: border-box;
 	}
 
@@ -1253,8 +1223,6 @@ table.form-table td .updated p {
 
 	#pass-strength-result {
 		width: 100%;
-		-webkit-box-sizing: border-box;
-		-moz-box-sizing: border-box;
 		box-sizing: border-box;
 		padding: 8px;
 	}
@@ -1347,7 +1315,6 @@ table.form-table td .updated p {
 	.wp-pwd button.button {
 		background: transparent;
 		border: none;
-		-webkit-box-shadow: none;
 		box-shadow: none;
 		line-height: 2;
 		margin: 0;
diff --git a/src/wp-admin/css/install.css b/src/wp-admin/css/install.css
index 9de99ee366..0b717730c4 100644
--- a/src/wp-admin/css/install.css
+++ b/src/wp-admin/css/install.css
@@ -11,7 +11,6 @@ body {
 	padding: 20px 20px 10px 20px;
 	max-width: 700px;
 	-webkit-font-smoothing: subpixel-antialiased;
-	-webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.13);
 	box-shadow: 0 1px 3px rgba(0,0,0,0.13);
 }
 
@@ -26,9 +25,6 @@ a:active {
 
 a:focus {
 	color: #124964;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -93,7 +89,6 @@ label {
 #logo a {
 	background-image: url(../images/w-logo-blue.png?ver=20131202);
 	background-image: none, url(../images/wordpress-logo.svg?ver=20131107);
-	-webkit-background-size: 84px;
 	background-size: 84px;
 	background-position: center top;
 	background-repeat: no-repeat;
@@ -113,7 +108,6 @@ label {
 }
 
 #logo a:focus {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -134,8 +128,6 @@ textarea {
 	border: 1px solid #ddd;
 	font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
 	width: 100%;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -175,7 +167,6 @@ textarea {
 	font-size: 15px;
 	padding: 3px 5px;
 	border: 1px solid #ddd;
-	-webkit-box-shadow: inset 0 1px 2px rgba(0,0,0,0.07);
 	box-shadow: inset 0 1px 2px rgba(0,0,0,0.07);
 }
 
@@ -237,8 +228,6 @@ submit {
 	padding: 3px 5px;
 	text-align: center;
 	width: 218px;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	opacity: 0;
 }
@@ -386,8 +375,6 @@ body.rtl,
 		padding: 7px 10px;
 		display: block;
 		max-width: none;
-		-webkit-box-sizing: border-box;
-		-moz-box-sizing: border-box;
 		box-sizing: border-box;
 	}
 
@@ -427,7 +414,6 @@ body.language-chooser {
 
 .spinner {
 	background: url(../images/spinner.gif) no-repeat;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 	visibility: hidden;
 	opacity: 0.7;
diff --git a/src/wp-admin/css/list-tables.css b/src/wp-admin/css/list-tables.css
index 05e5f82ad1..58ec28f162 100644
--- a/src/wp-admin/css/list-tables.css
+++ b/src/wp-admin/css/list-tables.css
@@ -49,14 +49,11 @@
 .column-response .comment-count-approved,
 .column-comments .comment-count-no-comments,
 .column-comments .comment-count-approved {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	display: block;
 	padding: 0 8px;
 	min-width: 24px;
 	height: 2em;
-	-webkit-border-radius: 5px;
 	border-radius: 5px;
 	background-color: #72777c;
 	color: #fff;
@@ -108,7 +105,6 @@
 	min-width: 7px;
 	height: 17px;
 	border: 2px solid #fff;
-	-webkit-border-radius: 11px;
 	border-radius: 11px;
 	background: #ca4a1f;
 	color: #fff;
@@ -208,7 +204,6 @@
 
 #replycontent {
 	height: 120px;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -250,13 +245,11 @@
 
 #the-comment-list th,
 #the-comment-list td {
-	-webkit-box-shadow: inset 0 -1px 0 rgba(0, 0, 0, 0.1);
 	box-shadow: inset 0 -1px 0 rgba(0, 0, 0, 0.1);
 }
 
 #the-comment-list tr:last-child th,
 #the-comment-list tr:last-child td {
-    -webkit-box-shadow: none;
     box-shadow: none;
 }
 
@@ -384,14 +377,12 @@ table.media .column-title .filename {
 
 /* @todo: pick a consistent list table selector */
 .wp-list-table a {
-	-webkit-transition: none;
 	transition: none;
 }
 
 #the-list tr:last-child td,
 #the-list tr:last-child th {
 	border-bottom: none !important;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -511,9 +502,6 @@ th.asc a:focus span.sorting-indicator:before {
 }
 
 .wp-list-table .toggle-row:focus:before {
-    -webkit-box-shadow:
-    	0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
     box-shadow:
     	0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -524,7 +512,6 @@ th.asc a:focus span.sorting-indicator:before {
 }
 
 .wp-list-table .toggle-row:active {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -532,7 +519,6 @@ th.asc a:focus span.sorting-indicator:before {
 	position: absolute;
 	top: -5px;
 	left: 10px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	display: block;
 	padding: 1px 2px 1px 0;
@@ -589,7 +575,6 @@ tr.wp-locked .locked-info {
 }
 
 tr.locked-info, tr.wp-locked .locked-info {
-	-webkit-transition: height 1s, opacity 0.5s;
 	transition: height 1s, opacity 0.5s;
 }
 
@@ -715,7 +700,6 @@ th.asc a:focus span.sorting-indicator {
 	border-color: #5b9dd9;
 	color: #fff;
 	background: #00a0d2;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none; /* IE8 */
 }
@@ -1277,7 +1261,6 @@ ul.cat-checklist {
 .plugin-install #the-list td,
 .upgrade .plugins td,
 .upgrade .plugins th {
-	-webkit-box-shadow: inset 0 -1px 0 rgba(0,0,0,0.1);
 	box-shadow: inset 0 -1px 0 rgba(0,0,0,0.1);
 }
 
@@ -1286,7 +1269,6 @@ ul.cat-checklist {
 .plugins tr.active + tr.inactive th,
 .plugins tr.active + tr.inactive td {
 	border-top: 1px solid rgba(0,0,0,0.03);
-	-webkit-box-shadow: inset 0 1px 0 rgba(0,0,0,0.02), inset 0 -1px 0 #e1e1e1;
 	box-shadow: inset 0 1px 0 rgba(0,0,0,0.02), inset 0 -1px 0 #e1e1e1;
 }
 
@@ -1300,7 +1282,6 @@ ul.cat-checklist {
 .plugins .updated th,
 .plugins tr.active + tr.inactive.updated th,
 .plugins tr.active + tr.inactive.updated td {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1343,7 +1324,6 @@ ul.cat-checklist {
 }
 
 .plugins .plugin-update-tr .plugin-update {
-	-webkit-box-shadow: inset 0 -1px 0 rgba(0,0,0,0.1);
 	box-shadow: inset 0 -1px 0 rgba(0,0,0,0.1);
 	overflow: hidden; /* clearfix */
 	padding: 0;
@@ -1429,12 +1409,9 @@ ul.cat-checklist {
 	float: left;
 	margin: 0 8px 16px;
 	width: 48.5%;
-	width: -webkit-calc( 50% - 8px );
 	width: calc( 50% - 8px );
 	background-color: #fff;
 	border: 1px solid #ddd;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -1450,7 +1427,6 @@ ul.cat-checklist {
 @media screen and ( min-width: 1600px ) {
 	.plugin-card {
 		width: 30%;
-		width: -webkit-calc( 33.1% - 8px );
 		width: calc( 33.1% - 8px );
 	}
 
@@ -1534,7 +1510,6 @@ div.action-links,
 .plugin-card-update-failed .notice-error {
 	margin: 0;
 	padding-left: 16px;
-	-webkit-box-shadow: 0 -1px 0 #ddd;
 	box-shadow: 0 -1px 0 #ddd;
 }
 
@@ -1564,7 +1539,6 @@ div.action-links,
 	float: right;
 	clear: right;
 	width: 65%;
-	width: -webkit-calc( 100% - 180px );
 	width: calc( 100% - 180px );
 }
 
@@ -1837,12 +1811,10 @@ div.action-links,
 	}
 
 	#the-comment-list .is-expanded td {
-		-webkit-box-shadow: none;
 		box-shadow: none;
 	}
 
 	#the-comment-list .is-expanded td:last-child {
-		-webkit-box-shadow: inset 0 -1px 0 rgba(0, 0, 0, 0.1);
 		box-shadow: inset 0 -1px 0 rgba(0, 0, 0, 0.1);
 	}
 
@@ -1891,7 +1863,6 @@ div.action-links,
 		min-width: 0;
 		padding: 0;
 		border: none;
-		-webkit-border-radius: 0;
 		border-radius: 0;
 		background: none;
 		color: #bb2a2a;
@@ -1941,8 +1912,6 @@ div.action-links,
 		display: block;
 		width: 100%;
 		max-width: none;
-		-webkit-box-sizing: border-box;
-		-moz-box-sizing: border-box;
 		box-sizing: border-box;
 	}
 
@@ -2055,7 +2024,6 @@ div.action-links,
 	.plugins #the-list .update th,
 	.plugins #the-list .update td,
 	.wp-list-table.plugins #the-list .theme-title {
-		-webkit-box-shadow: none;
 		box-shadow: none;
 		border-top: none;
 	}
@@ -2071,7 +2039,6 @@ div.action-links,
 	.plugins tr.active + tr.inactive th.check-column,
 	.plugins tr.active + tr.inactive td.column-description,
 	.plugins .plugin-update-tr:before {
-		-webkit-box-shadow: inset 0 -1px 0 rgba(0, 0, 0, 0.1);
 		box-shadow: inset 0 -1px 0 rgba(0, 0, 0, 0.1);
 	}
 
@@ -2136,13 +2103,11 @@ div.action-links,
 	}
 
 	table.plugin-install #the-list td {
-		-webkit-box-shadow: none;
 		box-shadow: none;
 	}
 
 	table.plugin-install #the-list tr {
 		display: block;
-		-webkit-box-shadow: inset 0 -1px 0 rgba(0,0,0,0.1);
 		box-shadow: inset 0 -1px 0 rgba(0,0,0,0.1);
 	}
 
diff --git a/src/wp-admin/css/login.css b/src/wp-admin/css/login.css
index 9da5f6b749..23283235d7 100644
--- a/src/wp-admin/css/login.css
+++ b/src/wp-admin/css/login.css
@@ -19,11 +19,8 @@ body {
 
 a {
 	color: #0073aa;
-	-webkit-transition-property: border, background, color;
 	transition-property: border, background, color;
-	-webkit-transition-duration: .05s;
 	transition-duration: .05s;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 }
 
@@ -38,9 +35,6 @@ a:active {
 
 a:focus {
 	color: #124964;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -61,7 +55,6 @@ p {
 	margin-left: 0;
 	margin-bottom: 20px;
 	background-color: #fff;
-	-webkit-box-shadow: 0 1px 1px 0 rgba(0,0,0,0.1);
 	box-shadow: 0 1px 1px 0 rgba(0,0,0,0.1);
 }
 
@@ -87,7 +80,6 @@ p {
 	font-weight: 400;
 	overflow: hidden;
 	background: #fff;
-	-webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.13);
 	box-shadow: 0 1px 3px rgba(0,0,0,0.13);
 }
 
@@ -127,7 +119,6 @@ p {
 .login h1 a {
 	background-image: url(../images/w-logo-blue.png?ver=20131202);
 	background-image: none, url(../images/wordpress-logo.svg?ver=20131107);
-	-webkit-background-size: 84px;
 	background-size: 84px;
 	background-position: center top;
 	background-repeat: no-repeat;
@@ -204,7 +195,6 @@ p {
 }
 
 .login-action-rp input[type="text"] {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	margin: 0;
 }
diff --git a/src/wp-admin/css/media.css b/src/wp-admin/css/media.css
index 288ece04e5..e629aa8e7b 100644
--- a/src/wp-admin/css/media.css
+++ b/src/wp-admin/css/media.css
@@ -124,7 +124,6 @@
 
 .media-upload-form .media-item,
 .media-upload-form .media-item .error {
-	-webkit-box-shadow: 0 1px 0 #ddd;
 	box-shadow: 0 1px 0 #ddd;
 }
 
@@ -163,10 +162,8 @@
 	line-height: 2em;
 	padding: 0;
 	overflow: hidden;
-	-webkit-border-radius: 22px;
 	border-radius: 22px;
 	background: #ddd;
-	-webkit-box-shadow: inset 0 1px 2px rgba(0,0,0,0.1);
 	box-shadow: inset 0 1px 2px rgba(0,0,0,0.1);
 }
 
@@ -175,10 +172,8 @@
 	width: 0;
 	height: 100%;
 	margin-top: -22px;
-	-webkit-border-radius: 22px;
 	border-radius: 22px;
 	background-color: #0073aa;
-	-webkit-box-shadow: inset 0 0 2px rgba(0,0,0,0.3);
 	box-shadow: inset 0 0 2px rgba(0,0,0,0.3);
 }
 
@@ -228,7 +223,6 @@
 
 .find-box {
 	background-color: #fff;
-	-webkit-box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	width: 600px;
 	overflow: hidden;
@@ -263,8 +257,6 @@
 	bottom: 45px;
 	overflow-y: scroll;
 	width: 100%;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -320,9 +312,6 @@
 
 #find-posts-close:focus {
 	outline: none;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -472,7 +461,6 @@ border color while dragging a file over the uploader drop area */
 	margin-top: 12px;
 	padding: 0 16px;
 	border-left: 4px solid #dd3d36;
- 	-webkit-box-shadow: 0 1px 1px 0 rgba(0, 0, 0, 0.1);
  	box-shadow: 0 1px 1px 0 rgba(0, 0, 0, 0.1);
 	background-color: #fff;
 }
@@ -491,7 +479,6 @@ border color while dragging a file over the uploader drop area */
 	margin: 12px 0;
 	padding: 4px 0 0;
 	border: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	background: none;
 }
@@ -539,9 +526,6 @@ border color while dragging a file over the uploader drop area */
 .media-frame.mode-grid .attachment:focus,
 .media-frame.mode-grid .selected.attachment:focus,
 .media-frame.mode-grid .attachment.details:focus {
-	-webkit-box-shadow:
-		inset 0 0 2px 3px #f1f1f1,
-		inset 0 0 0 7px #5b9dd9;
 	box-shadow:
 		inset 0 0 2px 3px #f1f1f1,
 		inset 0 0 0 7px #5b9dd9;
@@ -549,18 +533,12 @@ border color while dragging a file over the uploader drop area */
 }
 
 .media-frame.mode-grid .selected.attachment {
-	-webkit-box-shadow:
-		inset 0 0 0 5px #f1f1f1,
-		inset 0 0 0 7px #ccc;
 	box-shadow:
 		inset 0 0 0 5px #f1f1f1,
 		inset 0 0 0 7px #ccc;
 }
 
 .media-frame.mode-grid .attachment.details {
-	-webkit-box-shadow:
-		inset 0 0 0 3px #f1f1f1,
-		inset 0 0 0 7px #1e8cbe;
 	box-shadow:
 		inset 0 0 0 3px #f1f1f1,
 		inset 0 0 0 7px #1e8cbe;
@@ -663,7 +641,6 @@ border color while dragging a file over the uploader drop area */
 	text-align: center;
 	border: 0;
 	border-left: 1px solid #ddd;
-	-webkit-transition: color .1s ease-in-out, background .1s ease-in-out;
 	transition: color .1s ease-in-out, background .1s ease-in-out;
 }
 
@@ -702,7 +679,6 @@ border color while dragging a file over the uploader drop area */
 	border-color: #ccc;
 	color: #000;
 	outline: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -749,7 +725,6 @@ border color while dragging a file over the uploader drop area */
 	bottom: 0;
 	right: 0;
 	left: 0;
-	-webkit-box-shadow: inset 0px 4px 4px -4px rgba(0, 0, 0, 0.1);
 	box-shadow: inset 0px 4px 4px -4px rgba(0, 0, 0, 0.1);
 }
 
@@ -760,8 +735,6 @@ border color while dragging a file over the uploader drop area */
 }
 
 .edit-attachment-frame .attachment-media-view .thumbnail {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	padding: 16px;
 	height: 100%;
@@ -772,7 +745,6 @@ border color while dragging a file over the uploader drop area */
 	margin: 0 auto 16px;
 	max-width: 100%;
 	max-height: 90%;
-	max-height: -webkit-calc( 100% - 42px );
 	max-height: calc( 100% - 42px ); /* leave space for actions underneath */
 }
 
@@ -792,14 +764,11 @@ border color while dragging a file over the uploader drop area */
 
 .edit-attachment-frame .attachment-info {
 	overflow: auto;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	margin-bottom: 0;
 	padding: 12px 16px 0;
 	width: 35%;
 	height: 100%;
-	-webkit-box-shadow: inset 0px 4px 4px -4px rgba(0, 0, 0, 0.1);
 	box-shadow: inset 0px 4px 4px -4px rgba(0, 0, 0, 0.1);
 	border-bottom: 0;
 	border-left: 1px solid #ddd;
@@ -915,7 +884,6 @@ border color while dragging a file over the uploader drop area */
 	top: 50%;
 	margin: -10px 0 0 -10px;
 	background: transparent url(../images/spinner.gif) no-repeat center;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 	-webkit-transform: translateZ(0);
 	transform: translateZ(0);
@@ -1093,10 +1061,7 @@ border color while dragging a file over the uploader drop area */
 	font-size: 20px;
 	line-height: 1;
 	cursor: pointer;
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1104,7 +1069,6 @@ border color while dragging a file over the uploader drop area */
 	color: #0074a2;
 	border-color: #5b9dd9;
 	outline: none;
-	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
diff --git a/src/wp-admin/css/nav-menus.css b/src/wp-admin/css/nav-menus.css
index f9d2dec497..5d9459911e 100644
--- a/src/wp-admin/css/nav-menus.css
+++ b/src/wp-admin/css/nav-menus.css
@@ -606,7 +606,6 @@ body.menu-max-depth-11 { min-width: 1280px !important; }
 	margin-top: 10px;
 	margin-left: 4px;
 	width: 20px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	text-indent: -1px; /* account for the dashicon alignment */
 }
@@ -620,14 +619,10 @@ body.menu-max-depth-11 { min-width: 1280px !important; }
 }
 
 .nav-menus-php .item-edit:focus {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
 .nav-menus-php .item-edit:focus:before {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -646,7 +641,6 @@ body.menu-max-depth-11 { min-width: 1280px !important; }
 	z-index: 10; /* Keep .item-title's shadow from appearing on top of .menu-item-settings */
 	border: 1px solid #e5e5e5;
 	border-top: none;
-	-webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 	box-shadow: 0 1px 1px rgba(0,0,0,0.04);
 }
 
diff --git a/src/wp-admin/css/press-this.css b/src/wp-admin/css/press-this.css
index 49afa0e80b..bafea24d14 100644
--- a/src/wp-admin/css/press-this.css
+++ b/src/wp-admin/css/press-this.css
@@ -21,8 +21,6 @@ body {
 *,
 *:before,
 *:after {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 @media only screen and (-webkit-min-device-pixel-ratio: 1.5), only screen and (min-resolution: 144dpi) {
@@ -131,8 +129,6 @@ figure {
 }
 
 hr {
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
 	height: 0;
 }
@@ -193,8 +189,6 @@ input {
 
 input[type="checkbox"],
 input[type="radio"] {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	padding: 0;
 }
@@ -206,8 +200,6 @@ input[type="number"]::-webkit-outer-spin-button {
 
 input[type="search"] {
 	-webkit-appearance: textfield;
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
 }
 
@@ -331,7 +323,6 @@ strong {
 	padding: 0 10px 1px;
 	border-width: 1px;
 	border-style: solid;
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
 	font-size: 13px;
 	line-height: 2;
@@ -359,7 +350,6 @@ strong {
 	margin: 0;
 	padding: 8px;
 	list-style: none;
-	-webkit-box-shadow: 1px 0 4px rgba( 0, 0, 0, 0.15 );
 	box-shadow: 1px 0 4px rgba( 0, 0, 0, 0.15 );
 }
 
@@ -400,7 +390,6 @@ strong {
 	color: inherit;
 	text-decoration: none;
 	outline: none;
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -415,7 +404,6 @@ strong {
 
 .split-button-primary,
 .split-button-toggle {
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	display: block;
 	margin: 0;
@@ -430,8 +418,7 @@ strong {
 	border-color: #0073aa #006799 #006799;
 	border-width: 1px;
 	border-style: solid;
-	-webkit-box-shadow: 0 1px 0 #006799;
- 	box-shadow: 0 1px 0 #006799;
+ box-shadow: 0 1px 0 #006799;
 	color: #fff;
 	text-shadow: 0 -1px 1px #006799,
 		1px 0 1px #006799,
@@ -440,9 +427,7 @@ strong {
 }
 
 .split-button-primary {
-	-webkit-border-top-left-radius: 3px;
 	border-top-left-radius: 3px;
-	-webkit-border-bottom-left-radius: 3px;
 	border-bottom-left-radius: 3px;
 	border-right: 0 none;
 	float: left;
@@ -450,9 +435,7 @@ strong {
 
 .split-button-toggle {
 	padding: 0;
-	-webkit-border-top-right-radius: 3px;
 	border-top-right-radius: 3px;
-	-webkit-border-bottom-right-radius: 3px;
 	border-bottom-right-radius: 3px;
 	border-left: 1px solid #006799;
 	float: right;
@@ -473,8 +456,6 @@ strong {
 .split-button-primary:focus,
 .split-button-toggle:focus {
 	outline: none;
-	-webkit-box-shadow: 0 1px 0 #0073aa,
-		0 0 2px 1px #33b3db;
 	box-shadow: 0 1px 0 #0073aa,
 		0 0 2px 1px #33b3db;
 }
@@ -483,8 +464,7 @@ strong {
 .split-button-toggle:active {
 	background: #0073aa;
 	border-color: #006799;
-	-webkit-box-shadow: inset 0 2px 10px #006799, 0 1px 0 #0073aa;
- 	box-shadow: inset 0 2px 10px #006799, 0 1px 0 #0073aa;
+ box-shadow: inset 0 2px 10px #006799, 0 1px 0 #0073aa;
 }
 
 /**
@@ -509,8 +489,6 @@ textarea {
 
 [type="search"] {
 	-webkit-appearance: textfield;
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
 }
 
@@ -652,7 +630,6 @@ dd {
 	font-style: normal;
 	vertical-align: top;
 	text-align: center;
-	-webkit-transition: color .1s ease-in 0;
 	transition: color .1s ease-in 0;
 	-webkit-font-smoothing: antialiased;
 	-moz-osx-font-smoothing: grayscale;
@@ -669,7 +646,6 @@ dd {
 }
 
 .post-format:checked + .post-format-icon {
-	-webkit-box-shadow: inset 6px 0 0 #00a0d2;
 	box-shadow: inset 6px 0 0 #00a0d2;
 	background: rgba(46, 162, 204, 0.1);
 }
@@ -763,13 +739,11 @@ dd {
 	right: 0;
 	bottom: 1px;
 	border: 0;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	margin: 0;
 	padding: 0 16px;
 	background: #f7f7f7;
 	border-left: 1px solid #f1f1f1;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -780,7 +754,6 @@ dd {
 	background: #2991b7;
 	border-color: #20708e;
 	color: #fff;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -841,7 +814,6 @@ dd {
 	margin-left: 2px;
 	height: 20px;
 	width: 20px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	background: transparent;
 	color: #0073aa;
@@ -861,9 +833,6 @@ dd {
 }
 
 .tagchecklist .ntdelbutton:focus .remove-tag-icon:before {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -933,7 +902,6 @@ input[type="search"].categories-search,
 	width: 100%;
 	padding: 0.85714em 1.07143em;
 	border: 0;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	border-bottom: 1px solid #e5e5e5;
 	font-size: 14px;
@@ -957,7 +925,6 @@ input[type="search"].categories-search,
 	padding: 12px 10px 8px;
 	color: #0073aa;
 	text-decoration: none;
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -987,7 +954,6 @@ input[type="search"].categories-search,
 	top: 0;
 	right: 0;
 	border: 0;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	padding: 12px 16px;
 	background: #f7f7f7;
@@ -1014,11 +980,9 @@ input[type="search"].categories-search,
 	width: 100%;
 	height: 34px;
 	border: 0;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	border: 1px solid #e5e5e5;
 	background: #fff;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 	overflow: hidden;
 	line-height: 21px;
@@ -1032,7 +996,6 @@ input[type="search"].categories-search,
 
 .postform:focus {
 	border-color: #0073aa;
-	-webkit-box-shadow: 0 0 0 3px #00a0d2;
 	box-shadow: 0 0 0 3px #00a0d2;
 	outline: 0;
 	-moz-outline: none;
@@ -1082,7 +1045,6 @@ input[type="search"].categories-search,
 }
 
 .category.selected {
-	-webkit-box-shadow: inset 6px 0 0 #00a0d2;
 	box-shadow: inset 6px 0 0 #00a0d2;
 	background: #E9F5F9;
 }
@@ -1105,7 +1067,6 @@ input[type="search"].categories-search,
 	font-style: normal;
 	vertical-align: top;
 	text-align: center;
-	-webkit-transition: color .1s ease-in 0;
 	transition: color .1s ease-in 0;
 	-webkit-font-smoothing: antialiased;
 	-moz-osx-font-smoothing: grayscale;
@@ -1179,7 +1140,6 @@ body {
 
 html {
 	background: #fff;
-	-webkit-box-shadow: -10px 0 0 rgba(0, 0, 0, 0.3);
 	box-shadow: -10px 0 0 rgba(0, 0, 0, 0.3);
 }
 
@@ -1231,7 +1191,6 @@ html {
 	padding: 0 10px 1px;
 	font-size: 13px;
 	text-decoration: none;
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -1338,7 +1297,6 @@ html {
 	width: 8px;
 	height: 8px;
 	margin-top: -4px;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	background: #00a0d2;
 }
@@ -1363,7 +1321,6 @@ html {
 
 @media (max-width: 900px) {
 	.scan form {
-		-webkit-transition: opacity .3s ease-in-out;
 		transition: opacity .3s ease-in-out;
 	}
 	.scan.is-hidden form {
@@ -1396,7 +1353,6 @@ html {
 	border-color: #ddd;
 	border: 0;
 	border-left: 1px solid #f1f1f1;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	color: #555;
 	font-size: 14px;
@@ -1472,7 +1428,6 @@ html {
 	display: inline-block;
 	visibility: hidden;
 	background: url(../images/spinner.gif) no-repeat center;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 	opacity: 0.7;
 	filter: alpha(opacity=70);
@@ -1526,7 +1481,6 @@ html {
 .post-title-placeholder:active,
 .post-title-placeholder:focus {
 	outline: 0;
-	-webkit-box-shadow: inset 0px -3px 0 #00a0d2;
 	box-shadow: inset 0px -3px 0 #00a0d2;
 	border-color: #00a0d2;
 }
@@ -1636,7 +1590,6 @@ html {
 .suggested-media-thumbnail:focus,
 .is-embed:focus {
 	outline: 0;
-	-webkit-box-shadow: inset 0 0 0 3px #00a0d2;
 	box-shadow: inset 0 0 0 3px #00a0d2;
 }
 
@@ -1648,7 +1601,6 @@ html {
 	padding: 16.66% 0 0 16.66%;
 	background-position: center;
 	background-repeat: no-repeat;
-	-webkit-background-size: cover;
 	background-size: cover;
 	background-color: #d8d8d8;
 	color: #fff;
@@ -1672,7 +1624,6 @@ html {
 	text-decoration: inherit;
 	font-weight: 400;
 	font-style: normal;
-	-webkit-transition: color .1s ease-in 0;
 	transition: color .1s ease-in 0;
 	-webkit-font-smoothing: antialiased;
 	-moz-osx-font-smoothing: grayscale;
@@ -1763,16 +1714,13 @@ html {
 @media (max-width: 900px) {
 	.press-this-actions {
 		-webkit-transform: translateY(0);
-		-ms-transform: translateY(0);
 		transform: translateY(0);
-		-webkit-transition: -webkit-transform .3s ease-in-out;
 		transition: -webkit-transform .3s ease-in-out;
 		transition: transform .3s ease-in-out;
 		transition: transform .3s ease-in-out, -webkit-transform .3s ease-in-out;
 	}
 	.press-this-actions.is-hidden {
 		-webkit-transform: translateY(100%);
-		-ms-transform: translateY(100%);
 		transform: translateY(100%);
 	}
 }
@@ -1795,10 +1743,8 @@ html {
 	margin: 0;
 	padding: 0;
 	border: 0;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	background: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	overflow: hidden;
 }
@@ -1813,9 +1759,6 @@ html {
 .insert-media:active {
 	outline: 0;
 	color: #00a0d2;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -1952,7 +1895,6 @@ html {
 	border-left: 1px solid #e5e5e5;
 	font-size: 14px;
 	/* Keeps background the full height of the screen, but only visually. Clicks go through. */
-	-webkit-box-shadow: 5001px 5000px 0 5000px #fff, 5000px 5000px 0 5000px #e5e5e5;
 	box-shadow: 5001px 5000px 0 5000px #fff, 5000px 5000px 0 5000px #e5e5e5;
 	outline: 0;
 }
@@ -1970,9 +1912,7 @@ html {
 	.options-panel {
 		background: #fff;
 		-webkit-transform: translateX(-100%);
-		-ms-transform: translateX(-100%);
 		transform: translateX(-100%);
-		-webkit-transition: -webkit-transform .3s ease-in-out;
 		transition: -webkit-transform .3s ease-in-out;
 		transition: transform .3s ease-in-out;
 		transition: transform .3s ease-in-out, -webkit-transform .3s ease-in-out;
@@ -1984,7 +1924,6 @@ html {
 
 	.options-panel.is-off-screen {
 		-webkit-transform: translateX(0);
-		-ms-transform: translateX(0);
 		transform: translateX(0);
 	}
 }
@@ -1994,7 +1933,6 @@ html {
 		margin-right: -100%;
 		width: 100%;
 		border: 0;
-		-webkit-box-shadow: 5001px 5000px 0 5000px #fff;
 		box-shadow: 5001px 5000px 0 5000px #fff;
 	}
 
@@ -2055,7 +1993,6 @@ html {
 	text-overflow: ellipsis;
 	white-space: nowrap;
 	overflow: hidden;
-	-webkit-transition: -webkit-transform .3s ease-in-out;
 	transition: -webkit-transform .3s ease-in-out;
 	transition: transform .3s ease-in-out;
 	transition: transform .3s ease-in-out, -webkit-transform .3s ease-in-out;
@@ -2063,7 +2000,6 @@ html {
 
 .post-options .post-option:focus {
 	outline: 0;
-	-webkit-box-shadow: inset 5px 0 0 #00a0d2;
 	box-shadow: inset 5px 0 0 #00a0d2;
 	border-color: #e5e5e5;
 }
@@ -2080,7 +2016,6 @@ html {
 	.is-off-screen > .post-option {
 		right: auto;
 		-webkit-transform: translateX(-100%);
-		-ms-transform: translateX(-100%);
 		transform: translateX(-100%);
 	}
 }
@@ -2098,7 +2033,6 @@ html {
 	left: 0;
 	width: 100%;
 	overflow: hidden;
-	-webkit-transition: -webkit-transform .3s ease-in-out;
 	transition: -webkit-transform .3s ease-in-out;
 	transition: transform .3s ease-in-out;
 	transition: transform .3s ease-in-out, -webkit-transform .3s ease-in-out;
@@ -2117,7 +2051,6 @@ html {
 	.setting-modal.is-off-screen {
 		left: 0;
 		-webkit-transform: translateX(100%);
-		-ms-transform: translateX(100%);
 		transform: translateX(100%);
 	}
 }
@@ -2136,7 +2069,6 @@ html {
 
 .press-this .modal-close:focus {
 	outline: 0;
-	-webkit-box-shadow: inset 5px 0 0 #00a0d2;
 	box-shadow: inset 5px 0 0 #00a0d2;
 	border-color: #e5e5e5;
 }
@@ -2193,12 +2125,10 @@ html {
 /* Inline link dialog */
 .wp-link-input input {
 	border: 1px solid #ddd;
-    -webkit-box-shadow: inset 0 1px 2px rgba( 0, 0, 0, 0.07 );
     box-shadow: inset 0 1px 2px rgba( 0, 0, 0, 0.07 );
     background-color: #fff;
     color: #32373c;
     outline: none;
-    -webkit-transition: 0.05s border-color ease-in-out;
     transition: 0.05s border-color ease-in-out;
 }
 
@@ -2210,7 +2140,6 @@ html {
 	position: absolute;
 	z-index: 10000;
 	border: 1px solid #5b9dd9;
-	-webkit-box-shadow: 0 1px 2px rgba( 30, 140, 190, 0.8 );
 	box-shadow: 0 1px 2px rgba( 30, 140, 190, 0.8 );
 	background-color: #fff;
 	font-size: 14px;
diff --git a/src/wp-admin/css/revisions.css b/src/wp-admin/css/revisions.css
index 6ae57ef8d4..236d76244a 100644
--- a/src/wp-admin/css/revisions.css
+++ b/src/wp-admin/css/revisions.css
@@ -23,7 +23,6 @@
 	top: 0;
 	height: 82px;
 	background: #fff;
-	-webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.1);
 	box-shadow: 0 1px 3px rgba(0,0,0,0.1);
 }
 
@@ -33,8 +32,6 @@
 	height: 0.7em;
 	top: 7px;
 	max-width: 70%;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	background-color: #fff;
 }
@@ -43,8 +40,6 @@
 	position: absolute;
 	height: 100%;
 	border-left: 1px solid #a0a5aa;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -77,12 +72,9 @@
 	vertical-align: middle;
 	opacity: 0;
 	width: 100%;
-	width: -webkit-calc( 100% - 30px );
 	width: calc( 100% - 30px );
 	top: 50%;
-	top: -webkit-calc( 50% - 10px );
 	top: calc( 50% - 10px );
-	-webkit-transition: opacity 0.5s;
 	transition: opacity 0.5s;
 	filter: alpha(opacity=0); /* ie8 and earlier */
 }
@@ -103,7 +95,6 @@ body.folded .revisions .loading-indicator {
 }
 
 .revisions .diff {
-	-webkit-transition: opacity 0.5s;
 	transition: opacity 0.5s;
 }
 
@@ -119,12 +110,10 @@ body.folded .revisions .loading-indicator {
 .revisions-meta {
 	margin-top: 20px;
 	background-color: #fff;
-	-webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.1);
 	box-shadow: 0 1px 3px rgba(0,0,0,0.1);
 }
 
 .revisions.pinned .revisions-meta {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -183,7 +172,6 @@ body.folded .revisions .loading-indicator {
 .revisions-diff {
 	padding: 15px;
 	background-color: #fff;
-	-webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.1);
 	box-shadow: 0 1px 3px rgba(0,0,0,0.1);
 }
 
@@ -368,7 +356,6 @@ table.diff .diff-addedline ins {
 	width: 25px;
 	height: 25px;
 	-webkit-transform: rotate(45deg);
-	-ms-transform: rotate(45deg);
 	transform: rotate(45deg);
 }
 
@@ -411,7 +398,6 @@ table.diff .diff-addedline ins {
 .arrow:after {
 	z-index: 9999;
 	background-color: #fff;
-	-webkit-box-shadow: 0 1px 3px rgba(0,0,0,0.1);
 	box-shadow: 0 1px 3px rgba(0,0,0,0.1);
 }
 
@@ -432,7 +418,6 @@ table.diff .diff-addedline ins {
 	width: 25px;
 	height: 25px;
 	-webkit-transform: rotate(45deg);
-	-ms-transform: rotate(45deg);
 	transform: rotate(45deg);
 }
 
@@ -459,7 +444,6 @@ div.revisions-controls > .wp-slider > .ui-slider-handle {
 }
 
 .wp-slider .ui-slider-handle {
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	height: 18px;
 	margin-top: -5px;
@@ -468,7 +452,6 @@ div.revisions-controls > .wp-slider > .ui-slider-handle {
 	position: absolute;
 	width: 18px;
 	z-index: 2;
-	-ms-touch-action: none;
 	touch-action: none;
 }
 
@@ -476,7 +459,6 @@ div.revisions-controls > .wp-slider > .ui-slider-handle {
 .wp-slider .ui-slider-handle.focus {
 	background: #f7f7f7;
 	border: 1px solid #ccc;
-	-webkit-box-shadow: 0 1px 0 #cccccc;
 	box-shadow: 0 1px 0 #cccccc;
 }
 
@@ -490,10 +472,8 @@ div.revisions-controls > .wp-slider > .ui-slider-handle {
 .wp-slider .ui-slider-handle.ui-state-active {
 	background: #eee;
 	border-color: #999;
- 	-webkit-box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
  	box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
  	-webkit-transform: translateY(1px);
- 	-ms-transform: translateY(1px);
  	transform: translateY(1px);
 }
 
diff --git a/src/wp-admin/css/site-icon.css b/src/wp-admin/css/site-icon.css
index a4ac1ed2c3..eae9a57635 100644
--- a/src/wp-admin/css/site-icon.css
+++ b/src/wp-admin/css/site-icon.css
@@ -30,7 +30,6 @@
 
 .site-icon-preview .app-icon-preview {
 	background-color: #000;
-	-webkit-border-radius: 16px;
 	border-radius: 16px;
 	height: 64px;
 	overflow: hidden;
diff --git a/src/wp-admin/css/themes.css b/src/wp-admin/css/themes.css
index 7aadbee438..6c4ce8716a 100644
--- a/src/wp-admin/css/themes.css
+++ b/src/wp-admin/css/themes.css
@@ -56,10 +56,7 @@
 	position: relative;
 	width: 30.6%;
 	border: 1px solid #ddd;
-	-webkit-box-shadow: 0 1px 1px -1px rgba(0,0,0,0.1);
 	box-shadow: 0 1px 1px -1px rgba(0,0,0,0.1);
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -83,7 +80,6 @@
 	height: 18px;
 	margin: 0;
 	padding: 15px;
-	-webkit-box-shadow: inset 0 1px 0 rgba(0,0,0,0.1);
 	box-shadow: inset 0 1px 0 rgba(0,0,0,0.1);
 	overflow: hidden;
 	white-space: nowrap;
@@ -96,7 +92,6 @@
 .theme-browser .theme .theme-actions {
 	-ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)";
 	opacity: 0;
-	-webkit-transition: opacity 0.1s ease-in-out;
 	transition: opacity 0.1s ease-in-out;
 	position: absolute;
 	bottom: 0;
@@ -134,7 +129,6 @@
 	overflow: hidden;
 	position: relative;
 	-webkit-backface-visibility: hidden; /* Prevents flicker of the screenshot on hover. */
-	-webkit-transition: opacity 0.2s ease-in-out;
 	transition: opacity 0.2s ease-in-out;
 }
 
@@ -150,7 +144,6 @@
 	left: 0;
 	top: 0;
 	width: 100%;
-	-webkit-transition: opacity 0.2s ease-in-out;
 	transition: opacity 0.2s ease-in-out;
 }
 
@@ -180,15 +173,12 @@
 	font-weight: 600;
 	padding: 15px 12px;
 	text-align: center;
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
-	-webkit-transition: opacity 0.1s ease-in-out;
 	transition: opacity 0.1s ease-in-out;
 }
 
 .theme-browser .theme:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 2px rgba( 30, 140, 190, 0.8 );
 	box-shadow: 0 0 2px rgba( 30, 140, 190, 0.8 );
 }
 
@@ -215,7 +205,6 @@
 	color: #fff;
 	padding-right: 110px;
 	font-weight: 300;
-	-webkit-box-shadow: inset 0 1px 1px rgba(0,0,0,0.5);
 	box-shadow: inset 0 1px 1px rgba(0,0,0,0.5);
 }
 
@@ -262,7 +251,6 @@
  */
 .theme-browser .theme.add-new-theme {
 	border: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -287,15 +275,12 @@
 	text-shadow: none;
 	border: 5px dashed #d5d2ca;
 	border: 5px dashed rgba(0, 0, 0, 0.1);
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
 .theme-browser .theme.add-new-theme span:after {
 	background: #e5e5e5;
 	background: rgba(153, 153, 153, 0.1);
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	display: inline-block;
 	content: "\f132";
@@ -342,7 +327,6 @@
 .theme-browser .theme.add-new-theme .theme-name {
 	background: none;
 	text-align: center;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	font-weight: 400;
 	position: relative;
@@ -395,7 +379,6 @@
 	border: 0;
 	border-left: 1px solid #ddd;
 	background-color: transparent;
-	-webkit-transition: color .1s ease-in-out, background .1s ease-in-out;
 	transition: color .1s ease-in-out, background .1s ease-in-out;
 }
 
@@ -419,7 +402,6 @@
 	text-align: center;
 	border: 0;
 	border-right: 1px solid #ddd;
-	-webkit-transition: color .1s ease-in-out, background .1s ease-in-out;
 	transition: color .1s ease-in-out, background .1s ease-in-out;
 }
 
@@ -442,7 +424,6 @@
 .theme-overlay .theme-header .close:focus,
 .theme-overlay .theme-header .right:focus,
 .theme-overlay .theme-header .left:focus {
-    -webkit-box-shadow: none;
     box-shadow: none;
     outline: none;
 }
@@ -479,11 +460,8 @@
 	right: 30px;
 	bottom: 3%;
 	background: #fff;
-	-webkit-box-shadow: 0 1px 20px 5px rgba(0, 0, 0, 0.1);
 	box-shadow: 0 1px 20px 5px rgba(0, 0, 0, 0.1);
 	z-index: 10000; /* Over WP Pointers. */
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	-webkit-overflow-scrolling: touch;
 }
@@ -511,8 +489,6 @@ body.folded .theme-browser ~ .theme-overlay .theme-wrap {
 	padding: 10px 25px 5px;
 	background: #f3f3f3;
 	z-index: 30;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	border-top: 1px solid #eee;
 }
@@ -537,7 +513,6 @@ body.folded .theme-browser ~ .theme-overlay .theme-wrap {
 	color: #a00;
 	text-decoration: none;
 	border-color: transparent;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	background: transparent;
 }
@@ -581,12 +556,9 @@ body.folded .theme-browser ~ .theme-overlay .theme-wrap {
 /* First screenshot, shown big */
 .theme-overlay .screenshot {
 	border: 1px solid #fff;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	overflow: hidden;
 	position: relative;
-	-webkit-box-shadow: 0 0 0 1px rgba(0,0,0,0.2);
 	box-shadow: 0 0 0 1px rgba(0,0,0,0.2);
 }
 
@@ -670,7 +642,6 @@ body.folded .theme-browser ~ .theme-overlay .theme-wrap {
 	font-size: 11px;
 	display: inline-block;
 	padding: 2px 8px;
-	-webkit-border-radius: 2px;
 	border-radius: 2px;
 	margin: 0 0 -10px;
 	-webkit-user-select: none;
@@ -1039,8 +1010,6 @@ body.folded .theme-browser ~ .theme-overlay .theme-wrap {
 
 .upload-theme,
 .upload-plugin {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	display: none;
 	margin: 0;
@@ -1182,14 +1151,12 @@ div#custom-background-image img {
 .background-position-control input[type="radio"]:checked ~ .button {
 	background: #eee;
 	border-color: #999;
-	-webkit-box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, .5 );
 	box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, .5 );
 	z-index: 1;
 }
 
 .background-position-control input[type="radio"]:focus ~ .button {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, .5 ), 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, .5 ), 0 0 3px rgba( 0, 115, 170, .8 );
 	color: #23282d;
 }
@@ -1199,7 +1166,6 @@ div#custom-background-image img {
 	display: inline-block;
 	line-height: 1;
 	text-align: center;
-	-webkit-transition: background-color .1s ease-in 0;
 	transition: background-color .1s ease-in 0;
 }
 
@@ -1212,7 +1178,6 @@ div#custom-background-image img {
 
 .background-position-control .background-position-center-icon:before {
 	background-color: #555;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	content: "";
 	height: 12px;
@@ -1229,9 +1194,7 @@ div#custom-background-image img {
 }
 
 .background-position-control .button-group .button {
-	-webkit-border-radius: 0;
 	border-radius: 0;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	/* Following properties are overridden by buttons responsive styles (see: wp-includes/css/buttons.css). */
 	height: 40px !important;
@@ -1248,7 +1211,6 @@ div#custom-background-image img {
 }
 
 .background-position-control .button-group:last-child .button {
-	-webkit-box-shadow: 0 1px 0 #ccc;
 	box-shadow: 0 1px 0 #ccc;
 }
 
@@ -1257,46 +1219,38 @@ div#custom-background-image img {
 }
 
 .background-position-control .button-group:first-child > label:first-child .button {
-	-webkit-border-radius: 3px 0 0;
 	border-radius: 3px 0 0;
 }
 
 .background-position-control .button-group:first-child > label:first-child .dashicons {
 	-webkit-transform: rotate( 45deg );
-	-ms-transform: rotate( 45deg );
 	transform: rotate( 45deg );
 }
 
 .background-position-control .button-group:first-child > label:last-child .button {
-	-webkit-border-radius: 0 3px 0 0;
 	border-radius: 0 3px 0 0;
 }
 
 .background-position-control .button-group:first-child > label:last-child .dashicons {
 	-webkit-transform: rotate( -45deg );
-	-ms-transform: rotate( -45deg );
 	transform: rotate( -45deg );
 }
 
 .background-position-control .button-group:last-child > label:first-child .button {
-	-webkit-border-radius: 0 0 0 3px;
 	border-radius: 0 0 0 3px;
 }
 
 .background-position-control .button-group:last-child > label:first-child .dashicons {
 	-webkit-transform: rotate( -45deg );
-	-ms-transform: rotate( -45deg );
 	transform: rotate( -45deg );
 }
 
 .background-position-control .button-group:last-child > label:last-child .button {
-	-webkit-border-radius: 0 0 3px 0;
 	border-radius: 0 0 3px 0;
 }
 
 .background-position-control .button-group:last-child > label:last-child .dashicons {
 	-webkit-transform: rotate( 45deg );
-	-ms-transform: rotate( 45deg );
 	transform: rotate( 45deg );
 }
 
@@ -1332,8 +1286,6 @@ body.full-overlay-active {
 }
 
 .wp-full-overlay-sidebar {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	position: fixed;
 	min-width: 300px;
@@ -1417,7 +1369,6 @@ body.full-overlay-active {
 	z-index: 10;
 	margin: 0;
 	border-top: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1429,7 +1380,6 @@ body.full-overlay-active {
 	bottom: 0;
 	border-bottom: none;
 	border-top: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1461,7 +1411,6 @@ body.full-overlay-active {
 	color: #444;
 	cursor: pointer;
 	text-decoration: none;
-	-webkit-transition: color .1s ease-in-out, background .1s ease-in-out;
 	transition: color .1s ease-in-out, background .1s ease-in-out;
 }
 
@@ -1475,7 +1424,6 @@ body.full-overlay-active {
 	border-color: #ccc;
 	color: #000;
 	outline: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1542,9 +1490,7 @@ body.full-overlay-active {
 	line-height: 1;
 	background-color: transparent !important;
 	border: none !important;
-	-webkit-box-shadow: none !important;
 	box-shadow: none !important;
-	-webkit-border-radius: 0 !important;
 	border-radius: 0 !important;
 }
 
@@ -1564,16 +1510,12 @@ body.full-overlay-active {
 	width: 20px;
 	height: 20px;
 	margin: 0 2px; /* avoid the focus box-shadow to be cut-off */
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	overflow: hidden;
 }
 
 .wp-full-overlay .collapse-sidebar:hover .collapse-sidebar-arrow,
 .wp-full-overlay .collapse-sidebar:focus .collapse-sidebar-arrow {
-    -webkit-box-shadow:
-    	0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
     box-shadow:
     	0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -1606,13 +1548,11 @@ body.full-overlay-active {
 .wp-full-overlay.collapsed .collapse-sidebar-arrow:before,
 .rtl .wp-full-overlay .collapse-sidebar-arrow:before {
 	-webkit-transform: rotate(180.001deg);
-	-ms-transform: rotate(180.001deg);
 	transform: rotate(180.001deg); /* Firefox: promoting to its own layer to trigger anti-aliasing  */
 }
 
 .rtl .wp-full-overlay.collapsed .collapse-sidebar-arrow:before {
 	-webkit-transform: none;
-	-ms-transform: none;
 	transform: none;
 }
 
@@ -1621,9 +1561,7 @@ body.full-overlay-active {
 .wp-full-overlay-sidebar,
 .wp-full-overlay .collapse-sidebar,
 .wp-full-overlay-main {
-	-webkit-transition-property: left, right, top, bottom, width, margin;
 	transition-property: left, right, top, bottom, width, margin;
-	-webkit-transition-duration: 0.2s;
 	transition-duration: 0.2s;
 }
 
@@ -1644,7 +1582,6 @@ body.full-overlay-active {
 	min-width: 299px;
 	max-width: 599px;
 	width: 18%;
-	width: -webkit-calc( 18% - 1px );
 	width: calc( 18% - 1px );
 	height: 45px;
 	border-top: 1px solid #ddd;
@@ -1658,7 +1595,6 @@ body.full-overlay-active {
 .wp-full-overlay-footer .devices {
 	position: relative;
 	background: #eee;
-	-webkit-box-shadow: -20px 0 10px -5px #eee;
 	box-shadow: -20px 0 10px -5px #eee;
 }
 
@@ -1669,20 +1605,15 @@ body.full-overlay-active {
 	height: 45px;
 	padding: 0 3px;
 	margin: 0 0 0 -4px;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	border-top: 1px solid transparent;
 	border-bottom: 4px solid transparent;
-	-webkit-transition: .15s color ease-in-out,
-	            .15s background-color ease-in-out,
-	            .15s border-color ease-in-out;
 	transition: .15s color ease-in-out,
 	            .15s background-color ease-in-out,
 	            .15s border-color ease-in-out;
 }
 
 .wp-full-overlay-footer .devices button:focus {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 }
@@ -1802,7 +1733,6 @@ body.full-overlay-active {
 	height: 100%;
 	width: 100%;
 	z-index: 20;
-	-webkit-transition: opacity 0.3s;
 	transition: opacity 0.3s;
 }
 
@@ -1907,7 +1837,6 @@ body.full-overlay-active {
 	-webkit-transform: translateZ(0);
 	transform: translateZ(0);
 	background: transparent url(../images/spinner.gif) no-repeat center center;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 }
 
@@ -1927,7 +1856,6 @@ body.full-overlay-active {
   (min-resolution: 120dpi) {
 	.wp-full-overlay .collapse-sidebar-arrow {
 		background-image: url(../images/arrows-2x.png);
-		-webkit-background-size: 15px 123px;
 		background-size: 15px 123px;
 	}
 
diff --git a/src/wp-admin/css/widgets.css b/src/wp-admin/css/widgets.css
index cf02c7626b..627b581c72 100644
--- a/src/wp-admin/css/widgets.css
+++ b/src/wp-admin/css/widgets.css
@@ -3,8 +3,6 @@
 .widget {
 	margin: 0 auto 10px;
 	position: relative;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -84,8 +82,6 @@
 
 .media-widget-control .placeholder {
 	border: 1px dashed #b4b9be;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	cursor: default;
 	line-height: 20px;
@@ -170,8 +166,6 @@
 	margin: 0 auto 10px;
 	height: 45px;
 	width: 100%;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -188,8 +182,6 @@
 /* Widget Sidebars */
 .sidebar-name {
 	position: relative;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -270,7 +262,6 @@ div#widgets-left .widget-holder {
 
 #widgets-left .widgets-holder-wrap {
 	border: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -304,7 +295,6 @@ div#widgets-left .widget-holder {
 	padding: 0;
 	margin: 0 0 20px 0;
 	border: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -382,7 +372,6 @@ div#widgets-right .closed .widgets-sortables {
 /* Dragging a widget over a closed sidebar */
 #widgets-right .widgets-holder-wrap.widget-hover {
 	border-color: #72777c;
-	-webkit-box-shadow: 0 1px 2px rgba(0,0,0,0.3);
 	box-shadow: 0 1px 2px rgba(0,0,0,0.3);
 }
 
@@ -510,7 +499,6 @@ div#widgets-right .closed .widgets-sortables {
 /* Widgets Area Chooser */
 .widget-liquid-left #widgets-left.chooser #available-widgets .widget,
 .widget-liquid-left #widgets-left.chooser .inactive-sidebar {
-	-webkit-transition: opacity 0.1s linear;
 	transition: opacity 0.1s linear;
 }
 
@@ -533,7 +521,6 @@ div#widgets-right .closed .widgets-sortables {
 div#widgets-right .widget-top:hover,
 #widgets-left .widget-top:hover {
 	border-color: #999;
-	-webkit-box-shadow: 0 1px 2px rgba(0,0,0,0.1);
 	box-shadow: 0 1px 2px rgba(0,0,0,0.1);
 }
 
@@ -560,7 +547,6 @@ div#widgets-right .widget-top:hover,
 	cursor: pointer;
 	outline: none;
 	position: relative;
-	-webkit-transition: background 0.2s ease-in-out;
 	transition: background 0.2s ease-in-out;
 }
 
diff --git a/src/wp-includes/css/admin-bar.css b/src/wp-includes/css/admin-bar.css
index 523b5f72b7..9de2e6a4a0 100644
--- a/src/wp-includes/css/admin-bar.css
+++ b/src/wp-includes/css/admin-bar.css
@@ -11,12 +11,8 @@
 	font-weight: 400;
 	font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
 	line-height: 32px;
-	-webkit-border-radius: 0;
 	border-radius: 0;
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
-	-webkit-transition: none;
 	transition: none;
 	-webkit-font-smoothing: subpixel-antialiased; /* Prevent Safari from switching to standard antialiasing on hover */
 	-moz-osx-font-smoothing: auto; /* Prevent Firefox from inheriting from themes that use other values */
@@ -74,7 +70,6 @@ html:lang(he-il) .rtl #wpadminbar *  {
 #wpadminbar select,
 #wpadminbar textarea,
 #wpadminbar div {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 }
@@ -146,7 +141,6 @@ html:lang(he-il) .rtl #wpadminbar *  {
 #wpadminbar .shortlink-input {
 	margin: 0;
 	padding: 0;
-	-webkit-box-shadow: 0 3px 5px rgba(0,0,0,0.2);
 	box-shadow: 0 3px 5px rgba(0,0,0,0.2);
 	background: #32373c;
 	display: none;
@@ -257,7 +251,6 @@ html:lang(he-il) .rtl #wpadminbar *  {
 #wpadminbar .ab-item:before,
 #wpadminbar #adminbarsearch:before {
 	position: relative;
-	-webkit-transition: all .1s ease-in-out;
 	transition: all .1s ease-in-out;
 }
 
@@ -349,7 +342,6 @@ html:lang(he-il) .rtl #wpadminbar *  {
 	position: relative;
 	right: auto;
 	margin: 0;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -370,7 +362,6 @@ html:lang(he-il) .rtl #wpadminbar *  {
 	padding: 2px 5px;
 	font-size: 10px;
 	font-weight: 600;
-	-webkit-border-radius: 10px;
 	border-radius: 10px;
 }
 
@@ -385,7 +376,6 @@ html:lang(he-il) .rtl #wpadminbar *  {
 
 #wpadminbar ul li:last-child,
 #wpadminbar ul li:last-child .ab-item {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -644,16 +634,10 @@ html:lang(he-il) .rtl #wpadminbar *  {
 	border: none;
 	outline: none;
 	cursor: pointer;
-	-webkit-box-shadow: none;
 	box-shadow: none;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
-	-webkit-transition-duration: 400ms;
 	transition-duration: 400ms;
-	-webkit-transition-property: width, background;
 	transition-property: width, background;
-	-webkit-transition-timing-function: ease;
 	transition-timing-function: ease;
 }
 
@@ -734,7 +718,6 @@ html:lang(he-il) .rtl #wpadminbar *  {
 	z-index: 100000;
 	line-height: normal;
 	text-decoration: none;
-	-webkit-box-shadow: 0 0 2px 2px rgba(0,0,0,.6);
 	box-shadow: 0 0 2px 2px rgba(0,0,0,.6);
 }
 
@@ -1141,7 +1124,6 @@ html:lang(he-il) .rtl #wpadminbar *  {
 
 	#wpadminbar .ab-top-menu > .menupop li > .ab-sub-wrapper {
 		position: static;
-		-webkit-box-shadow: none;
 		box-shadow: none;
 	}
 }
diff --git a/src/wp-includes/css/buttons.css b/src/wp-includes/css/buttons.css
index 80ecd0718b..9b78343d9a 100644
--- a/src/wp-includes/css/buttons.css
+++ b/src/wp-includes/css/buttons.css
@@ -54,11 +54,8 @@ TABLE OF CONTENTS:
 	border-width: 1px;
 	border-style: solid;
 	-webkit-appearance: none;
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
 	white-space: nowrap;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -112,7 +109,6 @@ TABLE OF CONTENTS:
 .wp-core-ui input[type="reset"]:focus {
 	background: none;
 	border: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	padding: 0 2px 1px;
 	width: auto;
@@ -127,7 +123,6 @@ TABLE OF CONTENTS:
 	color: #555;
 	border-color: #cccccc;
 	background: #f7f7f7;
-	-webkit-box-shadow: 0 1px 0 #cccccc;
 	box-shadow: 0 1px 0 #cccccc;
  	vertical-align: top;
 }
@@ -151,7 +146,6 @@ TABLE OF CONTENTS:
 .wp-core-ui .button:focus,
 .wp-core-ui .button-secondary:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
@@ -161,18 +155,13 @@ TABLE OF CONTENTS:
 .wp-core-ui .button-secondary:active {
 	background: #eee;
 	border-color: #999;
-	-webkit-box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
 	box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
 	-webkit-transform: translateY(1px);
-	-ms-transform: translateY(1px);
 	transform: translateY(1px);
 }
 
 .wp-core-ui .button.active:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow:
-		inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 ),
-		0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow:
 		inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 ),
 		0 0 3px rgba( 0, 115, 170, .8 );
@@ -188,12 +177,10 @@ TABLE OF CONTENTS:
 	color: #a0a5aa !important;
 	border-color: #ddd !important;
 	background: #f7f7f7 !important;
-	-webkit-box-shadow: none !important;
 	box-shadow: none !important;
 	text-shadow: 0 1px 0 #fff !important;
 	cursor: default;
 	-webkit-transform: none !important;
-	-ms-transform: none !important;
 	transform: none !important;
 }
 
@@ -201,10 +188,8 @@ TABLE OF CONTENTS:
 .wp-core-ui .button-link {
 	margin: 0;
 	padding: 0;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	border: 0;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	background: none;
 	outline: none;
@@ -213,11 +198,8 @@ TABLE OF CONTENTS:
 	/* Mimics the default link style in common.css */
 	color: #0073aa;
 	text-decoration: underline;
-	-webkit-transition-property: border, background, color;
 	transition-property: border, background, color;
-	-webkit-transition-duration: .05s;
 	transition-duration: .05s;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 }
 
@@ -228,9 +210,6 @@ TABLE OF CONTENTS:
 
 .wp-core-ui .button-link:focus {
 	color: #124964;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -256,7 +235,6 @@ TABLE OF CONTENTS:
 .wp-core-ui .button-primary {
 	background: #0085ba;
 	border-color: #0073aa #006799 #006799;
-	-webkit-box-shadow: 0 1px 0 #006799;
 	box-shadow: 0 1px 0 #006799;
 	color: #fff;
 	text-decoration: none;
@@ -277,8 +255,6 @@ TABLE OF CONTENTS:
 
 .wp-core-ui .button-primary.focus,
 .wp-core-ui .button-primary:focus {
-	-webkit-box-shadow: 0 1px 0 #0073aa,
-		0 0 2px 1px #33b3db;
 	box-shadow: 0 1px 0 #0073aa,
 		0 0 2px 1px #33b3db;
 }
@@ -289,7 +265,6 @@ TABLE OF CONTENTS:
 .wp-core-ui .button-primary:active {
 	background: #0073aa;
 	border-color: #006799;
-	-webkit-box-shadow: inset 0 2px 0 #006799;
 	box-shadow: inset 0 2px 0 #006799;
 	vertical-align: top;
 }
@@ -301,23 +276,20 @@ TABLE OF CONTENTS:
 	color: #66c6e4 !important;
 	background: #008ec2 !important;
 	border-color: #007cb2 !important;
-	-webkit-box-shadow: none !important;
 	box-shadow: none !important;
 	text-shadow: 0 -1px 0 rgba( 0, 0, 0, 0.1 ) !important;
 	cursor: default;
 }
 
 .wp-core-ui .button.button-primary.button-hero {
-	-webkit-box-shadow: 0 2px 0 #006799;
- 	box-shadow: 0 2px 0 #006799;
+ box-shadow: 0 2px 0 #006799;
 }
 
 .wp-core-ui .button.button-primary.button-hero.active,
 .wp-core-ui .button.button-primary.button-hero.active:hover,
 .wp-core-ui .button.button-primary.button-hero.active:focus,
 .wp-core-ui .button.button-primary.button-hero:active {
-	-webkit-box-shadow: inset 0 3px 0 #006799;
- 	box-shadow: inset 0 3px 0 #006799;
+ box-shadow: inset 0 3px 0 #006799;
 }
 
 /* ----------------------------------------------------------------------------
@@ -334,7 +306,6 @@ TABLE OF CONTENTS:
 
 .wp-core-ui .button-group > .button {
 	display: inline-block;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 	margin-right: -1px;
 	z-index: 10;
@@ -349,12 +320,10 @@ TABLE OF CONTENTS:
 }
 
 .wp-core-ui .button-group > .button:first-child {
-	-webkit-border-radius: 3px 0 0 3px;
 	border-radius: 3px 0 0 3px;
 }
 
 .wp-core-ui .button-group > .button:last-child {
-	-webkit-border-radius: 0 3px 3px 0;
 	border-radius: 0 3px 3px 0;
 }
 
diff --git a/src/wp-includes/css/customize-preview.css b/src/wp-includes/css/customize-preview.css
index a4e24ea8d7..26c4a72cd4 100644
--- a/src/wp-includes/css/customize-preview.css
+++ b/src/wp-includes/css/customize-preview.css
@@ -1,13 +1,11 @@
 .customize-partial-refreshing {
 	opacity: 0.25;
-	-webkit-transition: opacity 0.25s;
 	transition: opacity 0.25s;
 	cursor: progress;
 }
 
 /* Override highlight when refreshing */
 .customize-partial-refreshing.widget-customizer-highlighted-widget {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -23,7 +21,6 @@
 	border: 0;
 	background: transparent;
 	color: transparent;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	outline: none;
 	z-index: 5;
@@ -48,15 +45,11 @@
 	font-size: 18px;
 	z-index: 5;
 	background: #0085ba !important;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	border: 2px solid #fff;
-	-webkit-box-shadow: 0 2px 1px rgba(46,68,83,0.15);
 	box-shadow: 0 2px 1px rgba(46,68,83,0.15);
 	text-align: center;
 	cursor: pointer;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	padding: 3px;
 	-webkit-animation-fill-mode: both;
@@ -88,7 +81,6 @@
 }
 
 .customize-partial-edit-shortcut button:focus {
-	-webkit-box-shadow: 0 0 0 2px #008ec2;
 	box-shadow: 0 0 0 2px #008ec2;
 }
 
diff --git a/src/wp-includes/css/dashicons.css b/src/wp-includes/css/dashicons.css
index 65e6de03ac..8436fa3cdc 100644
--- a/src/wp-includes/css/dashicons.css
+++ b/src/wp-includes/css/dashicons.css
@@ -25,7 +25,6 @@
 	font-style: normal;
 	vertical-align: top;
 	text-align: center;
-	-webkit-transition: color .1s ease-in 0;
 	transition: color .1s ease-in 0;
 	-webkit-font-smoothing: antialiased;
 	-moz-osx-font-smoothing: grayscale;
diff --git a/src/wp-includes/css/editor.css b/src/wp-includes/css/editor.css
index ca23b91c3e..e9f7842800 100644
--- a/src/wp-includes/css/editor.css
+++ b/src/wp-includes/css/editor.css
@@ -24,17 +24,13 @@
 #mce-modal-block.mce-fade {
 	opacity: 0.7;
 	filter: alpha(opacity=70);
-	-webkit-transition: none;
 	transition: none;
 }
 
 .mce-window {
-	-webkit-border-radius: 0;
 	border-radius: 0;
-	-webkit-box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	-webkit-font-smoothing: subpixel-antialiased;
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -86,14 +82,11 @@
 
 .mce-window-head .mce-close:focus .mce-i-remove,
 div.mce-tab:focus {
-	-webkit-box-shadow: 0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow: 0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
 }
 
 .mce-window .mce-window-head .mce-dragh {
-	width: -webkit-calc( 100% - 36px );
 	width: calc( 100% - 36px );
 }
 
@@ -105,11 +98,8 @@ div.mce-tab:focus {
 .mce-checkbox i.mce-i-checkbox,
 #wp-link .query-results {
 	border: 1px solid #ddd;
-	-webkit-border-radius: 0;
 	border-radius: 0;
-	-webkit-box-shadow: inset 0 1px 2px rgba(0,0,0,0.07);
 	box-shadow: inset 0 1px 2px rgba(0,0,0,0.07);
-	-webkit-transition: .05s all ease-in-out;
 	transition: .05s all ease-in-out;
 }
 
@@ -118,7 +108,6 @@ div.mce-tab:focus {
 .mce-checkbox:focus i.mce-i-checkbox,
 #wp-link .query-results:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 2px rgba(30,140,190,0.8);
 	box-shadow: 0 0 2px rgba(30,140,190,0.8);
 }
 
@@ -129,8 +118,6 @@ div.mce-tab:focus {
 }
 
 .mce-window .mce-wp-help * {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -209,9 +196,7 @@ div.mce-tab:focus {
 .mce-menu,
 .mce-floatpanel.mce-popover {
 	border-color: rgba(0,0,0,0.15);
-	-webkit-border-radius: 0;
 	border-radius: 0;
-	-webkit-box-shadow: 0 3px 5px rgba( 0, 0, 0, 0.2 );
 	box-shadow: 0 3px 5px rgba( 0, 0, 0, 0.2 );
 }
 
@@ -261,12 +246,8 @@ div.mce-toolbar-grp {
 
 div.mce-inline-toolbar-grp {
 	border: 1px solid #a0a5aa;
-	-webkit-border-radius: 2px;
 	border-radius: 2px;
-	-webkit-box-shadow: 0 1px 3px rgba( 0, 0, 0, 0.15 );
 	box-shadow: 0 1px 3px rgba( 0, 0, 0, 0.15 );
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	margin-bottom: 8px;
 	position: absolute;
@@ -393,7 +374,6 @@ div.mce-path {
 .qt-dfw {
 	border-color: transparent;
 	background: transparent;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	text-shadow: none;
 	cursor: pointer;
@@ -408,7 +388,6 @@ div.mce-path {
 .qt-dfw {
 	border: 1px solid transparent;
 	margin: 2px;
-	-webkit-border-radius: 2px;
 	border-radius: 2px;
 }
 
@@ -419,7 +398,6 @@ div.mce-path {
 	background: #fafafa;
 	border-color: #555d66;
 	color: #23282d;
-	-webkit-box-shadow: inset 0 1px 0 #fff, 0 1px 0 rgba( 0, 0, 0, 0.08 );
 	box-shadow: inset 0 1px 0 #fff, 0 1px 0 rgba( 0, 0, 0, 0.08 );
 	outline: none;
 }
@@ -429,7 +407,6 @@ div.mce-path {
 .qt-dfw.active {
 	background: #ebebeb;
 	border-color: #555d66;
-	-webkit-box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.3 );
 	box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.3 );
 }
 
@@ -444,7 +421,6 @@ div.mce-path {
 	background: none;
 	border-color: #ddd;
 	text-shadow: 0 1px 0 #fff;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -497,7 +473,6 @@ div.mce-path {
 	min-width: 0;
 	background: #0085ba;
 	border-color: #0073aa #006799 #006799;
-	-webkit-box-shadow: 0 1px 0 #006799;
 	box-shadow: 0 1px 0 #006799;
 	color: #fff;
 	text-decoration: none;
@@ -521,25 +496,21 @@ div.mce-path {
 }
 
 .mce-toolbar .mce-btn-group .mce-btn.mce-primary:focus {
-	-webkit-box-shadow: 0 0 1px 1px #33b3db;
 	box-shadow: 0 0 1px 1px #33b3db;
 }
 
 .mce-toolbar .mce-btn-group .mce-btn.mce-primary:active {
 	background: #0073aa;
 	border-color: #006799;
-	-webkit-box-shadow: inset 0 2px 0 #006799;
 	box-shadow: inset 0 2px 0 #006799;
 }
 
 /* mce listbox */
 .mce-toolbar .mce-btn-group .mce-btn.mce-listbox {
-    -webkit-border-radius: 0;
     border-radius: 0;
     direction: ltr;
     background: #fff;
     border: 1px solid #ddd;
-    -webkit-box-shadow: inset 0 1px 1px -1px rgba(0, 0, 0, .2);
     box-shadow: inset 0 1px 1px -1px rgba(0, 0, 0, .2);
 }
 
@@ -623,9 +594,6 @@ div.mce-menubar {
 
 .mce-menubar .mce-menubtn:focus {
 	color: #124964;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -679,10 +647,8 @@ div.mce-menu .mce-menu-item-sep,
 	cursor: pointer;
 	border: 1px solid #cccccc;
 	-webkit-appearance: none;
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
 	white-space: nowrap;
-	-webkit-box-shadow: 0 1px 0 #cccccc;
 	box-shadow: 0 1px 0 #cccccc;
 }
 
@@ -702,17 +668,14 @@ div.mce-menu .mce-menu-item-sep,
 
 .mce-window .mce-btn:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
 .mce-window .mce-btn:active {
 	background: #eee;
 	border-color: #999;
-	-webkit-box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
 	box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
 	-webkit-transform: translateY(1px);
-	-ms-transform: translateY(1px);
 	transform: translateY(1px);
 }
 
@@ -720,19 +683,16 @@ div.mce-menu .mce-menu-item-sep,
 	color: #a0a5aa !important;
 	border-color: #ddd !important;
 	background: #f7f7f7 !important;
-	-webkit-box-shadow: none !important;
 	box-shadow: none !important;
 	text-shadow: 0 1px 0 #fff !important;
 	cursor: default;
 	-webkit-transform: none !important;
-	-ms-transform: none !important;
 	transform: none !important;
 }
 
 .mce-window .mce-btn.mce-primary {
 	background: #0085ba;
 	border-color: #0073aa #006799 #006799;
-	-webkit-box-shadow: 0 1px 0 #006799;
 	box-shadow: 0 1px 0 #006799;
 	color: #fff;
 	text-decoration: none;
@@ -750,8 +710,6 @@ div.mce-menu .mce-menu-item-sep,
 }
 
 .mce-window .mce-btn.mce-primary:focus {
-	-webkit-box-shadow: 0 1px 0 #0073aa,
-		0 0 2px 1px #33b3db;
 	box-shadow: 0 1px 0 #0073aa,
 		0 0 2px 1px #33b3db;
 }
@@ -759,7 +717,6 @@ div.mce-menu .mce-menu-item-sep,
 .mce-window .mce-btn.mce-primary:active {
 	background: #0073aa;
 	border-color: #006799;
-	-webkit-box-shadow: inset 0 2px 0 #006799;
 	box-shadow: inset 0 2px 0 #006799;
 	vertical-align: top;
 }
@@ -768,7 +725,6 @@ div.mce-menu .mce-menu-item-sep,
 	color: #66c6e4 !important;
 	background: #008ec2 !important;
 	border-color: #007cb2 !important;
-	-webkit-box-shadow: none !important;
 	box-shadow: none !important;
 	text-shadow: 0 -1px 0 rgba( 0, 0, 0, 0.1 ) !important;
 	cursor: default;
@@ -807,9 +763,7 @@ div.mce-menu .mce-menu-item-sep,
 }
 
 .mce-tooltip-inner {
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
-	-webkit-box-shadow: 0 3px 5px rgba( 0, 0, 0, 0.2 );
 	box-shadow: 0 3px 5px rgba( 0, 0, 0, 0.2 );
 	color: #fff;
 	font-size: 12px;
@@ -1100,8 +1054,6 @@ i.mce-i-wp_code:before {
 	outline: none;
 	display: block;
 	resize: vertical;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -1116,7 +1068,6 @@ i.mce-i-wp_code:before {
 .wp-editor-container textarea.wp-editor-area {
 	width: 100%;
 	margin: 0;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1126,8 +1077,6 @@ i.mce-i-wp_code:before {
 
 .wp-switch-editor {
 	float: left;
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
 	position: relative;
 	top: 1px;
@@ -1143,9 +1092,6 @@ i.mce-i-wp_code:before {
 }
 
 .wp-switch-editor:focus {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -1156,13 +1102,11 @@ i.mce-i-wp_code:before {
 .wp-switch-editor:active,
 .html-active .switch-html:focus,
 .tmce-active .switch-tmce:focus {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
 .wp-switch-editor:active {
 	background-color: #f5f5f5;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1349,7 +1293,6 @@ i.mce-i-wp_code:before {
 	padding: 2px;
 	border-width: 1px;
 	border-style: solid;
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
 }
 
@@ -1368,7 +1311,6 @@ i.mce-i-wp_code:before {
 #wp-link-wrap {
 	display: none;
 	background-color: #fff;
-	-webkit-box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	width: 500px;
 	overflow: hidden;
@@ -1378,7 +1320,6 @@ i.mce-i-wp_code:before {
 	top: 50%;
 	left: 50%;
 	z-index: 100105;
-	-webkit-transition: height 0.2s, margin-top 0.2s;
 	transition: height 0.2s, margin-top 0.2s;
 }
 
@@ -1457,9 +1398,6 @@ i.mce-i-wp_code:before {
 
 #wp-link-close:focus {
 	outline: none;
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -1483,8 +1421,6 @@ i.mce-i-wp_code:before {
 }
 
 #wp-link input[type="text"] {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -1636,7 +1572,6 @@ i.mce-i-wp_code:before {
 #wp-link .item-title {
 	display: inline-block;
 	width: 80%;
-	width: -webkit-calc(100% - 68px);
 	width: calc(100% - 68px);
 	word-wrap: break-word;
 }
@@ -1725,7 +1660,6 @@ i.mce-i-wp_code:before {
 
 @media screen and ( max-height: 520px ) {
 	#wp-link-wrap {
-		-webkit-transition: none;
 		transition: none;
 		height: auto;
 		margin-top: 0;
@@ -1752,7 +1686,6 @@ i.mce-i-wp_code:before {
 
 	#link-selector {
 		overflow: auto;
-		height: -webkit-calc(100% - 92px);
 		height: calc(100% - 92px);
 		padding-bottom: 2px;
 	}
@@ -1773,11 +1706,8 @@ div.wp-link-preview {
 div.wp-link-preview a {
 	color: #0073aa;
 	text-decoration: underline;
-	-webkit-transition-property: border, background, color;
 	transition-property: border, background, color;
-	-webkit-transition-duration: .05s;
 	transition-duration: .05s;
-	-webkit-transition-timing-function: ease-in-out;
 	transition-timing-function: ease-in-out;
 	cursor: pointer;
 }
@@ -1795,8 +1725,6 @@ div.wp-link-input {
 div.wp-link-input input {
 	width: 300px;
 	padding: 3px;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -1818,7 +1746,6 @@ div.wp-link-input input {
 	list-style: none;
 	position: absolute;
 	border: 1px solid #5b9dd9;
-	-webkit-box-shadow: 0 1px 2px rgba( 30, 140, 190, 0.8 );
 	box-shadow: 0 1px 2px rgba( 30, 140, 190, 0.8 );
 	background-color: #fff;
 }
@@ -1844,7 +1771,6 @@ div.wp-link-input input {
 	div.wp-link-preview,
 	div.wp-link-input {
 		max-width: 70%;
-		max-width: -webkit-calc(100% - 86px);
 		max-width: calc(100% - 86px);
 	}
 
diff --git a/src/wp-includes/css/jquery-ui-dialog.css b/src/wp-includes/css/jquery-ui-dialog.css
index 111fecd638..0249f5100b 100644
--- a/src/wp-includes/css/jquery-ui-dialog.css
+++ b/src/wp-includes/css/jquery-ui-dialog.css
@@ -107,7 +107,6 @@
 	position: absolute;
 	font-size: 0.1px;
 	display: block;
-	-ms-touch-action: none;
 	touch-action: none;
 }
 .ui-resizable-disabled .ui-resizable-handle,
@@ -191,16 +190,12 @@
 	border-width: 1px;
 	border-style: solid;
 	-webkit-appearance: none;
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
 	white-space: nowrap;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	color: #555;
 	border-color: #cccccc;
 	background: #f7f7f7;
-	-webkit-box-shadow: 0 1px 0 #cccccc;
 	box-shadow: 0 1px 0 #cccccc;
  	vertical-align: top;
 }
@@ -226,17 +221,14 @@
 
 .ui-button:focus {
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
 .ui-button:active {
 	background: #eee;
 	border-color: #999;
-	-webkit-box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
 	box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
 	-webkit-transform: translateY(1px);
-	-ms-transform: translateY(1px);
 	transform: translateY(1px);
 }
 
@@ -245,12 +237,10 @@
 	color: #a0a5aa !important;
 	border-color: #ddd !important;
 	background: #f7f7f7 !important;
-	-webkit-box-shadow: none !important;
 	box-shadow: none !important;
 	text-shadow: 0 1px 0 #fff !important;
 	cursor: default;
 	-webkit-transform: none !important;
-	-ms-transform: none !important;
 	transform: none !important;
 }
 
@@ -275,7 +265,6 @@
 	left: 0;
 	z-index: 100102;
 	background-color: #fff;
-	-webkit-box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 }
 
@@ -292,7 +281,6 @@
 .ui-button.ui-dialog-titlebar-close {
 	background: none;
 	border: none;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	color: #666;
 	cursor: pointer;
diff --git a/src/wp-includes/css/media-views.css b/src/wp-includes/css/media-views.css
index 8b50e8fdd7..0a912a75d1 100644
--- a/src/wp-includes/css/media-views.css
+++ b/src/wp-includes/css/media-views.css
@@ -2,16 +2,12 @@
  * Base Styles
  */
 .media-modal * {
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
 }
 
 .media-modal input,
 .media-modal select,
 .media-modal textarea {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -49,9 +45,6 @@
 }
 
 .media-frame a:focus {
-	-webkit-box-shadow:
-		0 0 0 1px #5b9dd9,
-		0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow:
 		0 0 0 1px #5b9dd9,
 		0 0 2px 1px rgba(30, 140, 190, .8);
@@ -141,7 +134,6 @@
  */
 .ui-draggable-handle,
 .ui-sortable-handle {
-	-ms-touch-action: none;
 	touch-action: none;
 }
 
@@ -191,7 +183,6 @@
 	z-index: 1000;
 	cursor: pointer;
 	outline: none;
-	-webkit-transition: color .1s ease-in-out, background .1s ease-in-out;
 	transition: color .1s ease-in-out, background .1s ease-in-out;
 }
 
@@ -203,7 +194,6 @@
 .media-modal-close:focus {
 	color: #00a0d2;
 	border-color: #5b9dd9;
-	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
@@ -228,7 +218,6 @@
 	bottom: 0;
 	overflow: auto;
 	min-height: 300px;
-	-webkit-box-shadow: 0 5px 15px rgba(0,0,0,0.7);
 	box-shadow: 0 5px 15px rgba(0,0,0,0.7);
 	background: #fcfcfc;
 	-webkit-font-smoothing: subpixel-antialiased;
@@ -238,7 +227,6 @@
 	margin-top: 11px;
 	margin-right: 2%;
 	width: 42%;
-	width: -webkit-calc(48% - 12px);
 	width: calc(48% - 12px);
 }
 
@@ -440,8 +428,6 @@
 .attachment-details .setting input[type="url"],
 .attachment-details .setting textarea,
 .attachment-details .setting .value {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	margin: 1px;
 	width: 65%;
@@ -520,8 +506,6 @@
 .compat-item .field textarea {
 	width: 100%;
 	margin: 0;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -601,7 +585,6 @@
 }
 
 .media-router a {
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -728,7 +711,6 @@
 
 .media-frame.hide-router .media-frame-title {
 	border-bottom: 1px solid #ddd;
-	-webkit-box-shadow: 0 4px 4px -4px rgba( 0, 0, 0, 0.1 );
 	box-shadow: 0 4px 4px -4px rgba( 0, 0, 0, 0.1 );
 }
 
@@ -796,7 +778,6 @@
 	margin-top: 11px;
 	margin-right: 2%;
 	max-width: 42%;
-	max-width: -webkit-calc(48% - 12px);
 	max-width: calc(48% - 12px);
 }
 
@@ -845,17 +826,12 @@
 	-ms-user-select: none;
 	user-select: none;
 	width: 25%;
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
 .wp-core-ui .attachment:focus,
 .wp-core-ui .selected.attachment:focus,
 .wp-core-ui .attachment.details:focus {
-	-webkit-box-shadow:
-		inset 0 0 2px 3px #fff,
-		inset 0 0 0 7px #5b9dd9;
 	box-shadow:
 		inset 0 0 2px 3px #fff,
 		inset 0 0 0 7px #5b9dd9;
@@ -863,18 +839,12 @@
 }
 
 .wp-core-ui .selected.attachment {
-	-webkit-box-shadow:
-		inset 0 0 0 5px #fff,
-		inset 0 0 0 7px #ccc;
 	box-shadow:
 		inset 0 0 0 5px #fff,
 		inset 0 0 0 7px #ccc;
 }
 
 .wp-core-ui .attachment.details {
-	-webkit-box-shadow:
-		inset 0 0 0 3px #fff,
-		inset 0 0 0 7px #0073aa;
 	box-shadow:
 		inset 0 0 0 3px #fff,
 		inset 0 0 0 7px #0073aa;
@@ -882,9 +852,6 @@
 
 .wp-core-ui .attachment-preview {
 	position: relative;
-	-webkit-box-shadow:
-		inset 0 0 15px rgba( 0, 0, 0, 0.1 ),
-		inset 0 0 0 1px rgba( 0, 0, 0, 0.05 );
 	box-shadow:
 		inset 0 0 15px rgba( 0, 0, 0, 0.1 ),
 		inset 0 0 0 1px rgba( 0, 0, 0, 0.05 );
@@ -911,7 +878,6 @@
 	bottom: 0;
 	left: 0;
 	opacity: 1;
-	-webkit-transition: opacity .1s;
 	transition: opacity .1s;
 }
 
@@ -931,7 +897,6 @@
 	left: 0;
 	right: 0;
 	bottom: 0;
-	-webkit-box-shadow: inset 0 0 0 1px rgba( 0, 0, 0, 0.1 );
 	box-shadow: inset 0 0 0 1px rgba( 0, 0, 0, 0.1 );
 	overflow: hidden;
 }
@@ -947,20 +912,17 @@
 	left: 0;
 	width: 100%;
 	height: 100%;
-	-webkit-transform: translate( 50%, 50% );
-	-ms-transform: translate(50%,50%); /* Fails with spaces?? Weird! */
+	-webkit-transform: translate( 50%, 50% ); /* Fails with spaces?? Weird! */
 	transform: translate( 50%, 50% );
 }
 
 .wp-core-ui .attachment .thumbnail .centered img {
 	-webkit-transform: translate( -50%, -50% );
-	-ms-transform: translate(-50%,-50%);
 	transform: translate( -50%, -50% );
 }
 
 .wp-core-ui .attachments-browser .attachment .thumbnail .centered img.icon {
 	-webkit-transform: translate( -50%, -70% );
-	-ms-transform: translate(-50%,-70%);
 	transform: translate( -50%, -70% );
 }
 
@@ -980,7 +942,6 @@
 	text-align: center;
 	font-weight: 600;
 	background: rgba( 255, 255, 255, 0.8 );
-	-webkit-box-shadow: inset 0 0 0 1px rgba( 0, 0, 0, 0.15 );
 	box-shadow: inset 0 0 0 1px rgba( 0, 0, 0, 0.15 );
 }
 
@@ -1002,11 +963,8 @@
 	padding: 0;
 	background-color: #fff;
 	background-position: -96px 4px;
-	-webkit-border-radius: 3px;
 	border-radius: 3px;
-	-webkit-box-shadow: 0 0 0 1px rgba( 0, 0, 0, 0.3 );
 	box-shadow: 0 0 0 1px rgba( 0, 0, 0, 0.3 );
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -1028,7 +986,6 @@
 	outline: none;
 	background: #eee;
 	cursor: pointer;
-	-webkit-box-shadow: 0 0 0 1px #fff, 0 0 0 2px rgba( 0, 0, 0, 0.15 );
 	box-shadow: 0 0 0 1px #fff, 0 0 0 2px rgba( 0, 0, 0, 0.15 );
 }
 
@@ -1052,9 +1009,6 @@
 .wp-core-ui .attachment.selected .check:focus,
 .wp-core-ui .media-frame.mode-grid .attachment.selected .check {
 	background-color: #0073aa;
-	-webkit-box-shadow:
-		0 0 0 1px #fff,
-		0 0 0 2px #0073aa;
 	box-shadow:
 		0 0 0 1px #fff,
 		0 0 0 2px #0073aa;
@@ -1078,7 +1032,6 @@
 	margin: 0;
 	padding: 8px;
 	font-size: 12px;
-	-webkit-border-radius: 0;
 	border-radius: 0;
 }
 
@@ -1161,7 +1114,6 @@
 
 .uploader-inline .close:focus {
 	outline: 1px solid  #5b9dd9;
-	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
@@ -1192,7 +1144,6 @@
 	height: 10px;
 	width: 70%;
 	margin: 10px auto;
-	-webkit-border-radius: 10px;
 	border-radius: 10px;
 	background: #ddd;
 	background: rgba( 0, 0, 0, 0.1 );
@@ -1203,9 +1154,7 @@
 	min-width: 20px;
 	width: 0;
 	background: #0073aa;
-	-webkit-border-radius: 10px;
 	border-radius: 10px;
-	-webkit-transition: width 300ms;
 	transition: width 300ms;
 }
 
@@ -1275,7 +1224,6 @@
 	top: -10px;
 	right: -10px;
 	padding: 10px;
-	-webkit-transition: none;
 	transition: none;
 }
 
@@ -1296,13 +1244,11 @@
 	margin-bottom: 12px;
 	background: #fff;
 	border-left: 4px solid #dc3232;
-	-webkit-box-shadow: 0 1px 1px 0 rgba(0, 0, 0, 0.1);
 	box-shadow: 0 1px 1px 0 rgba(0, 0, 0, 0.1);
 }
 
 .uploader-inline .upload-errors .upload-error {
 	background-color: #fbeaea;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1327,7 +1273,6 @@
 	display: none;
 	text-align: center;
 	opacity: 0;
-	-webkit-transition: opacity 250ms;
 	transition: opacity 250ms;
 }
 
@@ -1348,7 +1293,6 @@
 	left: 0;
 	right: 0;
 	-webkit-transform: translateY( -50% );
-	-ms-transform: translateY(-50%);
 	transform: translateY( -50% );
 	font-size: 40px;
 	color: #fff;
@@ -1535,7 +1479,6 @@
 }
 
 .media-selection .attachment-preview {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	background: none;
 }
@@ -1543,23 +1486,16 @@
 .wp-core-ui .media-selection .attachment:focus,
 .wp-core-ui .media-selection .selected.attachment:focus,
 .wp-core-ui .media-selection .attachment.details:focus {
-	-webkit-box-shadow:
-		0 0 0 1px #fff,
-		0 0 2px 3px #5b9dd9;
 	box-shadow:
 		0 0 0 1px #fff,
 		0 0 2px 3px #5b9dd9;
 }
 
 .wp-core-ui .media-selection .selected.attachment {
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
 .wp-core-ui .media-selection .attachment.details {
-	-webkit-box-shadow:
-		0 0 0 1px #fff,
-		0 0 0 3px #0073aa;
 	box-shadow:
 		0 0 0 1px #fff,
 		0 0 0 3px #0073aa;
@@ -1573,8 +1509,6 @@
 	right: 0;
 	bottom: 0;
 	width: 25px;
-	background-image: -webkit-gradient(linear, right top, left top, from(rgba( 255, 255, 255, 1 )), to(rgba( 255, 255, 255, 0 )));
-	background-image: -webkit-linear-gradient(right, rgba( 255, 255, 255, 1 ), rgba( 255, 255, 255, 0 ));
 	background-image: linear-gradient(to left, rgba( 255, 255, 255, 1 ), rgba( 255, 255, 255, 0 ));
 }
 
@@ -1587,7 +1521,6 @@
  */
 .media-frame .spinner {
 	background: url(../images/spinner.gif) no-repeat;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 	float: right;
 	display: inline-block;
@@ -1668,7 +1601,6 @@
 .uploading .attachment-info .thumbnail {
 	width: 120px;
 	height: 80px;
-	-webkit-box-shadow: inset 0 0 15px rgba( 0, 0, 0, 0.1 );
 	box-shadow: inset 0 0 15px rgba( 0, 0, 0, 0.1 );
 }
 
@@ -1684,7 +1616,6 @@
 	left: 0;
 	right: 0;
 	bottom: 0;
-	-webkit-box-shadow: inset 0 0 0 1px rgba( 0, 0, 0, 0.15 );
 	box-shadow: inset 0 0 0 1px rgba( 0, 0, 0, 0.15 );
 	overflow: hidden;
 }
@@ -1795,7 +1726,6 @@
 	background: none;
 	border: none;
 	border-bottom: 1px solid #ddd;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 	margin: 0;
 	margin-bottom: 16px;
@@ -1844,10 +1774,7 @@
 	font-size: 20px;
 	line-height: 1;
 	cursor: pointer;
-	-webkit-box-sizing: content-box;
-	-moz-box-sizing: content-box;
 	box-sizing: content-box;
-	-webkit-box-shadow: none;
 	box-shadow: none;
 }
 
@@ -1855,7 +1782,6 @@
 	color: #0074a2;
 	border-color: #5b9dd9;
 	outline: none;
-	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
@@ -1903,7 +1829,6 @@
 	padding: 12px 14px;
 	width: 100%;
 	min-width: 200px;
-	-webkit-box-shadow: inset 2px 2px 4px -2px rgba( 0, 0, 0, 0.1 );
 	box-shadow: inset 2px 2px 4px -2px rgba( 0, 0, 0, 0.1 );
 }
 
@@ -1952,7 +1877,6 @@
 
 .mejs-container:focus {
 	outline: 1px solid #5b9dd9;
-	-webkit-box-shadow: 0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow: 0 0 2px 1px rgba(30, 140, 190, .8);
 }
 
@@ -1975,8 +1899,6 @@
 
 .image-details .embed-media-settings,
 .image-details .embed-media-settings div {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 }
 
@@ -2094,7 +2016,6 @@
 	left: 0;
 	right: 0;
 	bottom: 0;
-	-webkit-box-shadow: inset 0 0 0 1px rgba( 0, 0, 0, 0.1 );
 	box-shadow: inset 0 0 0 1px rgba( 0, 0, 0, 0.1 );
 	overflow: hidden;
 }
@@ -2209,7 +2130,6 @@
 	left: 0;
 	right: 0;
 	-webkit-transform: translateY( -50% );
-	-ms-transform: translateY(-50%);
 	transform: translateY( -50% );
 	font-size: 3em;
 	line-height: 1.3;
@@ -2549,8 +2469,6 @@
 		z-index: 1900;
 		max-width: 70%;
 		bottom: 120%;
-		-webkit-box-sizing: border-box;
-		-moz-box-sizing: border-box;
 		box-sizing: border-box;
 		padding-bottom: 0;
 	}
@@ -2658,7 +2576,6 @@
 
 	.wp-core-ui .media-modal-icon {
 		background-image: url(../images/uploader-icons-2x.png);
-		-webkit-background-size: 134px 15px;
 		background-size: 134px 15px;
 	}
 
diff --git a/src/wp-includes/css/wp-auth-check.css b/src/wp-includes/css/wp-auth-check.css
index 4047e17cf1..7be3663da5 100644
--- a/src/wp-includes/css/wp-auth-check.css
+++ b/src/wp-includes/css/wp-auth-check.css
@@ -30,7 +30,6 @@
 	padding: 30px 0 0;
 	background-color: #f1f1f1;
 	z-index: 1000011; /* needs to appear above #wp-auth-check-bg */
-	-webkit-box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 	box-shadow: 0 3px 6px rgba( 0, 0, 0, 0.3 );
 }
 
@@ -64,7 +63,6 @@
 	top: 50%;
 	margin: -10px 0 0 -10px;
 	background: url(../images/spinner.gif) no-repeat center;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px 20px;
 	-webkit-transform: translateZ(0);
 	transform: translateZ(0);
diff --git a/src/wp-includes/css/wp-embed-template.css b/src/wp-includes/css/wp-embed-template.css
index 28e437c411..306c835d55 100644
--- a/src/wp-includes/css/wp-embed-template.css
+++ b/src/wp-includes/css/wp-embed-template.css
@@ -23,10 +23,8 @@ body {
 	height: 20px;
 	background-color: transparent;
 	background-repeat: no-repeat;
-	-webkit-background-size: 20px 20px;
 	background-size: 20px;
 	background-position: center;
-	-webkit-transition: background .1s ease-in;
 	transition: background .1s ease-in;
 	position: relative;
 	top: 5px;
@@ -66,7 +64,6 @@ body {
 	color: #82878c;
 	background: #fff;
 	border: 1px solid #e5e5e5;
-	-webkit-box-shadow: 0 1px 1px rgba(0, 0, 0, .05);
 	box-shadow: 0 1px 1px rgba(0, 0, 0, .05);
 	/* Clearfix */
 	overflow: auto;
@@ -128,7 +125,6 @@ p.wp-embed-heading {
 	top: 50%;
 	left: 0;
 	-webkit-transform: translateY(-50%);
-	-ms-transform: translateY(-50%);
 	transform: translateY(-50%);
 	height: 25px;
 	width: 25px;
@@ -186,7 +182,6 @@ p.wp-embed-heading {
 	background-color: rgba(10, 10, 10, 0.9);
 	color: #fff;
 	opacity: 1;
-	-webkit-transition: opacity .25s ease-in-out;
 	transition: opacity .25s ease-in-out;
 }
 
@@ -216,9 +211,7 @@ p.wp-embed-heading {
 
 .wp-embed-share-dialog-open:focus .dashicons,
 .wp-embed-share-dialog-close:focus .dashicons {
-	-webkit-box-shadow: 0 0 0 1px #5b9dd9, 0 0 2px 1px rgba(30, 140, 190, .8);
 	box-shadow: 0 0 0 1px #5b9dd9, 0 0 2px 1px rgba(30, 140, 190, .8);
-	-webkit-border-radius: 100%;
 	border-radius: 100%;
 }
 
@@ -236,7 +229,6 @@ p.wp-embed-heading {
 .wp-embed-share-dialog-close .dashicons {
 	height: 24px;
 	width: 24px;
-	-webkit-background-size: 24px 24px;
 	background-size: 24px;
 }
 
@@ -271,7 +263,6 @@ p.wp-embed-heading {
 	line-height: 1.3;
 	color: #aaa;
 	cursor: pointer;
-	-webkit-transition: color .1s ease-in;
 	transition: color .1s ease-in;
 }
 
@@ -302,8 +293,6 @@ p.wp-embed-share-description {
 }
 
 .wp-embed-share-input {
-	-webkit-box-sizing: border-box;
-	-moz-box-sizing: border-box;
 	box-sizing: border-box;
 	width: 100%;
 	border: none;
diff --git a/src/wp-includes/css/wp-pointer.css b/src/wp-includes/css/wp-pointer.css
index bb1d6ebd50..ed37b8443c 100644
--- a/src/wp-includes/css/wp-pointer.css
+++ b/src/wp-includes/css/wp-pointer.css
@@ -4,7 +4,6 @@
 	font-size: 13px;
 	background: #fff;
 	border: 1px solid #ddd;
-	-webkit-box-shadow: 0 3px 6px rgba(0,0,0,0.075);
 	box-shadow: 0 3px 6px rgba(0,0,0,0.075);
 }
 
@@ -22,7 +21,6 @@
 
 .wp-pointer-content h3:before {
 	background: #fff;
-	-webkit-border-radius: 50%;
 	border-radius: 50%;
 	color: #00a0d2;
 	content: "\f227";