diff --git a/docs/4.0/examples/index.md b/docs/4.0/examples/index.md
index 344d5be300..8546a86987 100644
--- a/docs/4.0/examples/index.md
+++ b/docs/4.0/examples/index.md
@@ -14,14 +14,14 @@ Examples that focus on implementing uses of built-in components provided by Boot
 <div class="row bd-examples">
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/starter-template/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/starter-template.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/starter-template.jpg" alt="" width="800" height="600">
       <h4>Starter template</h4>
     </a>
     <p>Nothing but the basics: compiled CSS and JavaScript.</p>
   </div>
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/grid/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/grid.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/grid.jpg" alt="" width="800" height="600">
       <h4>Grids</h4>
     </a>
     <p>Multiple examples of grid layouts with all four tiers, nesting, and more.</p>
@@ -30,14 +30,14 @@ Examples that focus on implementing uses of built-in components provided by Boot
 
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/jumbotron/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/jumbotron.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/jumbotron.jpg" alt="" width="800" height="600">
       <h4>Jumbotron</h4>
     </a>
     <p>Build around the jumbotron with a navbar and some basic grid columns.</p>
   </div>
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/narrow-jumbotron/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/jumbotron-narrow.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/jumbotron-narrow.jpg" alt="" width="800" height="600">
       <h4>Narrow jumbotron</h4>
     </a>
     <p>Build a more custom page by narrowing the default container and jumbotron.</p>
@@ -51,14 +51,14 @@ Taking the default navbar component and showing how it can be moved, placed, and
 <div class="row bd-examples">
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/navbars/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/navbar.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/navbar.jpg" alt="" width="800" height="600">
       <h4>Navbar</h4>
     </a>
     <p>Super basic template that includes the navbar along with some additional content.</p>
   </div>
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/navbar-top/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/navbar-static.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/navbar-static.jpg" alt="" width="800" height="600">
       <h4>Static top navbar</h4>
     </a>
     <p>Super basic template with a static top navbar along with some additional content.</p>
@@ -67,11 +67,18 @@ Taking the default navbar component and showing how it can be moved, placed, and
 
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/navbar-top-fixed/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/navbar-fixed.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/navbar-fixed.jpg" alt="" width="800" height="600">
       <h4>Fixed navbar</h4>
     </a>
     <p>Super basic template with a fixed top navbar along with some additional content.</p>
   </div>
+  <div class="col-6 col-md-4">
+    <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/navbar-bottom/">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/navbar-bottom.jpg" alt="">
+      <h4>Bottom navbar</h4>
+    </a>
+    <p>Super basic template with a bottom navbar along with some additional content.</p>
+  </div>
 </div>
 
 ## Custom components
@@ -81,14 +88,14 @@ Brand new components and templates to help folks quickly get started with Bootst
 <div class="row bd-examples">
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/album/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/album.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/album.jpg" alt="" width="800" height="600">
       <h4>Album</h4>
     </a>
     <p>Simple one-page template for photo galleries, portfolios, and more.</p>
   </div>
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/cover/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/cover.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/cover.jpg" alt="" width="800" height="600">
       <h4>Cover</h4>
     </a>
     <p>A one-page template for building simple and beautiful home pages.</p>
@@ -97,14 +104,14 @@ Brand new components and templates to help folks quickly get started with Bootst
 
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/carousel/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/carousel.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/carousel.jpg" alt="" width="800" height="600">
       <h4>Carousel</h4>
     </a>
     <p>Customize the navbar and carousel, then add some new components.</p>
   </div>
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/blog/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/blog.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/blog.jpg" alt="" width="800" height="600">
       <h4>Blog</h4>
     </a>
     <p>Simple two-column blog layout with custom navigation, header, and type.</p>
@@ -113,14 +120,14 @@ Brand new components and templates to help folks quickly get started with Bootst
 
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/dashboard/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/dashboard.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/dashboard.jpg" alt="" width="800" height="600">
       <h4>Dashboard</h4>
     </a>
     <p>Basic admin dashboard shell with fixed sidebar and navbar.</p>
   </div>
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/signin/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/sign-in.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/sign-in.jpg" alt="" width="800" height="600">
       <h4>Sign-in page</h4>
     </a>
     <p>Custom form layout and design for a simple sign in form.</p>
@@ -129,14 +136,14 @@ Brand new components and templates to help folks quickly get started with Bootst
 
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/justified-nav/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/justified-nav.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/justified-nav.jpg" alt="" width="800" height="600">
       <h4>Justified nav</h4>
     </a>
     <p>Create a custom navbar with justified links. Heads up! Not too Safari friendly.</p>
   </div>
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/sticky-footer/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/sticky-footer.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/sticky-footer.jpg" alt="" width="800" height="600">
       <h4>Sticky footer</h4>
     </a>
     <p>Attach a footer to the bottom of the viewport when the content is shorter than it.</p>
@@ -145,7 +152,7 @@ Brand new components and templates to help folks quickly get started with Bootst
 
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/sticky-footer-navbar/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/sticky-footer-navbar.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/sticky-footer-navbar.jpg" alt="" width="800" height="600">
       <h4>Sticky footer w/ navbar</h4>
     </a>
     <p>Attach a footer to the bottom of the viewport with a fixed top navbar.</p>
@@ -159,7 +166,7 @@ Examples that focus on future-friendly features or techniques.
 <div class="row bd-examples">
   <div class="col-6 col-md-4">
     <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/offcanvas/">
-      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/offcanvas.jpg" alt="">
+      <img class="img-thumbnail" src="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/screenshots/offcanvas.jpg" alt="" width="800" height="600">
       <h4>Offcanvas</h4>
     </a>
     <p>Build a toggleable off-canvas navigation menu for use with Bootstrap.</p>
diff --git a/docs/4.0/examples/navbar-bottom/index.html b/docs/4.0/examples/navbar-bottom/index.html
new file mode 100644
index 0000000000..3046f9b9ba
--- /dev/null
+++ b/docs/4.0/examples/navbar-bottom/index.html
@@ -0,0 +1,60 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+    <meta name="description" content="">
+    <meta name="author" content="">
+    <link rel="icon" href="../../../../favicon.ico">
+
+    <title>Bottom navbar example for Bootstrap</title>
+
+    <!-- Bootstrap core CSS -->
+    <link href="../../../../dist/css/bootstrap.min.css" rel="stylesheet">
+  </head>
+
+  <body>
+    <div class="container">
+      <div class="jumbotron mt-3">
+        <h1>Bottom Navbar example</h1>
+        <p class="lead">This example is a quick exercise to illustrate how the bottom navbar works.</p>
+        <a class="btn btn-lg btn-primary" href="../../components/navbar/" role="button">View navbar docs &raquo;</a>
+      </div>
+    </div>
+    <nav class="navbar fixed-bottom navbar-expand navbar-dark bg-dark">
+      <a class="navbar-brand" href="#">Bottom navbar</a>
+      <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarCollapse" aria-controls="navbarCollapse" aria-expanded="false" aria-label="Toggle navigation">
+        <span class="navbar-toggler-icon"></span>
+      </button>
+      <div class="collapse navbar-collapse" id="navbarCollapse">
+        <ul class="navbar-nav mr-auto">
+          <li class="nav-item active">
+            <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
+          </li>
+          <li class="nav-item">
+            <a class="nav-link" href="#">Link</a>
+          </li>
+          <li class="nav-item">
+            <a class="nav-link disabled" href="#">Disabled</a>
+          </li>
+          <li class="nav-item dropup">
+            <a class="nav-link dropdown-toggle" href="https://getbootstrap.com" id="dropdown10" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Dropup</a>
+            <div class="dropdown-menu" aria-labelledby="dropdown10">
+              <a class="dropdown-item" href="#">Action</a>
+              <a class="dropdown-item" href="#">Another action</a>
+              <a class="dropdown-item" href="#">Something else here</a>
+            </div>
+          </li>
+        </ul>
+      </div>
+    </nav>
+
+    <!-- Bootstrap core JavaScript
+    ================================================== -->
+    <!-- Placed at the end of the document so the pages load faster -->
+    <script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
+    <script>window.jQuery || document.write('<script src="../../../../assets/js/vendor/jquery.min.js"><\/script>')</script>
+    <script src="../../../../assets/js/vendor/popper.min.js"></script>
+    <script src="../../../../dist/js/bootstrap.min.js"></script>
+  </body>
+</html>
diff --git a/docs/4.0/examples/screenshots/navbar-bottom.jpg b/docs/4.0/examples/screenshots/navbar-bottom.jpg
new file mode 100644
index 0000000000..c25c2f89cf
Binary files /dev/null and b/docs/4.0/examples/screenshots/navbar-bottom.jpg differ
diff --git a/scss/_navbar.scss b/scss/_navbar.scss
index 1398400c03..a0ccc06fb7 100644
--- a/scss/_navbar.scss
+++ b/scss/_navbar.scss
@@ -74,6 +74,13 @@
     position: static;
     float: none;
   }
+
+  .dropdown-toggle {
+    &::after {
+      border-top: $caret-width solid;
+      border-bottom: 0;
+    }
+  }
 }
 
 
@@ -144,6 +151,18 @@
           padding-right: 0;
           padding-left: 0;
         }
+
+        .dropup {
+          .dropdown-menu {
+            position: absolute;
+            top: auto;
+            bottom: 100%;
+          }
+
+          .dropdown-toggle {
+            @include caret(up);
+          }
+        }
       }
 
       @include media-breakpoint-up($next) {