Holy fucking shit fix that input group with buttons rounded corner noise

less/button-groups.less

@@ -16,7 +16,17 @@
   display: inline-block;
   vertical-align: middle; // match .btn alignment given font-size hack above
   > .btn {
+    position: relative;
     float: left;
+    // Prevent double borders when buttons are next to each other
+    + btn {
+      margin-left: -1px;
+    }
+    // Bring the "active" button to the front
+    &:hover,
+    &:active {
+      z-index: 2;
+    }
   }
 }
 
@@ -116,13 +126,14 @@
 .btn-group-vertical > .btn {
   display: block;
   float: none;
-  border-radius: 0;
   max-width: 100%;
 }
 .btn-group-vertical .btn:first-child {
+  border-radius: 0; // Needs to be here for specificity since we're not zeroing them out again
   .border-top-radius(@border-radius-base);
 }
 .btn-group-vertical .btn:last-child {
+  border-radius: 0; // Needs to be here for specificity since we're not zeroing them out again
   .border-bottom-radius(@border-radius-base);
 }
 .btn-group-vertical .btn-large:first-child {

less/buttons.less

@@ -19,6 +19,7 @@
   cursor: pointer;
   border: 1px solid @btn-border;
   border-radius: @border-radius-base;
+  white-space: nowrap;
 
   &:focus {
     .tab-focus();

less/forms.less

@@ -503,52 +503,43 @@ select:focus:invalid {
 
 // Button input groups
 // -------------------------
-.input-group-btn,
-.input-group-btn .btn {
+.input-group-btn {
+  position: relative;
   white-space: nowrap;
 }
 .input-group-btn > .btn {
+  position: relative;
   float: left; // Collapse white-space
   border-radius: 0;
   + .btn {
-    border-left: 0;
+    margin-left: -1px;
+  }
+  // Bring the "active" button to the front
+  &:hover,
+  &:active {
+    z-index: 2;
   }
 }
-.input-group-btn.btn-group {
-  display: table-cell;
-}
-// Prepend
-.input-group-btn {
-  &:first-child > .btn,
-  &.btn-group:first-child > .btn {
-    border-right: 0;
-  }
-  &:first-child > .btn,
-  &.btn-group:first-child > .btn {
-    border-radius: @border-radius-base 0 0 @border-radius-base;
-    &.btn-large {
-      border-radius:@border-radius-large 0 0 @border-radius-large;
-    }
-    &.btn-small {
-      border-radius:@border-radius-small 0 0 @border-radius-small;
-    }
+
+// Prepended buttons
+.input-group-btn:first-child {
+  // Round the left corners only
+  > .btn:first-child,
+  > .dropdown-toggle:first-child {
+    .border-left-radius(@border-radius-base);
+    &.btn-large { .border-left-radius(@border-radius-large); }
+    &.btn-small { .border-left-radius(@border-radius-small); }
   }
 }
-// Append
-.input-group-btn {
-  &:last-child > .btn,
-  &.btn-group:last-child > .btn:first-child {
-    border-left: 0;
-  }
-  &:last-child > .btn,
-  &.btn-group:last-child > .btn {
-    border-radius: 0 @border-radius-base @border-radius-base 0;
-    &.btn-large {
-      border-radius: 0 @border-radius-large @border-radius-large 0;
-    }
-    &.btn-small {
-      border-radius: 0 @border-radius-small @border-radius-small 0;
-    }
+
+// Appended buttons
+.input-group-btn:last-child {
+  // Round the right corners only
+  > .btn:last-child,
+  > .dropdown-toggle {
+    .border-right-radius(@border-radius-base);
+    &.btn-large { .border-right-radius(@border-radius-large); }
+    &.btn-small { .border-right-radius(@border-radius-small); }
   }
 }
 
@@ -557,7 +548,6 @@ select:focus:invalid {
 // Horizontal forms
 // --------------------------------------------------
 
-
 @media screen and (min-width: 768px) {
 
   .form-horizontal {