diff --git a/wp-admin/css/wp-admin.dev.css b/wp-admin/css/wp-admin.dev.css
index 8cec577bda..ca5339cee4 100644
--- a/wp-admin/css/wp-admin.dev.css
+++ b/wp-admin/css/wp-admin.dev.css
@@ -5131,7 +5131,7 @@ body.full-overlay-active {
 /* Collapse Button */
 .wp-full-overlay .collapse-sidebar {
 	position: absolute;
-	top: 13px;
+	bottom: 13px;
 	left: 265px;
 	z-index: 50;
 	display: block;
@@ -5144,7 +5144,7 @@ body.full-overlay-active {
 	position: absolute;
 	left: 315px;
 }
-.wp-full-overlay .collapse-sidebar span {
+.wp-full-overlay .collapse-sidebar-arrow {
 	margin-top: 2px;
 	margin-left: 2px;
 	display: block;
@@ -5152,10 +5152,25 @@ body.full-overlay-active {
 	height: 15px;
 	background: transparent url('../../wp-admin/images/arrows.png') no-repeat 0 -72px;
 }
-.wp-full-overlay.collapsed .collapse-sidebar span {
+.wp-full-overlay.collapsed .collapse-sidebar-arrow {
 	background-position: 0 -108px;
 }
 
+.wp-full-overlay .collapse-sidebar-label {
+	text-align: right;
+	position: absolute;
+	right: 100%;
+	color: #aaa;
+	line-height: 20px;
+	margin-right: 10px;
+}
+.wp-full-overlay.collapsed .collapse-sidebar-label {
+	display: none;
+}
+.wp-full-overlay .collapse-sidebar:hover .collapse-sidebar-label {
+	color: #999;
+}
+
 /* Animations */
 .wp-full-overlay,
 .wp-full-overlay .collapse-sidebar,
@@ -5193,6 +5208,10 @@ body.full-overlay-active {
 	z-index: 20;
 }
 
+#customize-container .collapse-sidebar {
+	bottom: 16px;
+}
+
 #theme-installer {
 	display: none;
 }
diff --git a/wp-admin/includes/class-wp-theme-install-list-table.php b/wp-admin/includes/class-wp-theme-install-list-table.php
index 578935b889..4dc0b61191 100644
--- a/wp-admin/includes/class-wp-theme-install-list-table.php
+++ b/wp-admin/includes/class-wp-theme-install-list-table.php
@@ -213,10 +213,14 @@ class WP_Theme_Install_List_Table extends WP_Themes_List_Table {
 		?>
 		<div id="theme-installer" class="wp-full-overlay">
 			<a href="#" class="close-full-overlay"><?php printf( __( '&larr; Return to %s' ), get_admin_page_title() ); ?></a>
-			<a href="#" class="collapse-sidebar button-secondary" title="<?php esc_attr_e('Collapse Sidebar'); ?>"><span></span></a>
+			<a href="#" class="collapse-sidebar button-secondary" title="<?php esc_attr_e('Collapse Sidebar'); ?>">
+				<span class="collapse-sidebar-label"><?php _e('Collapse'); ?></span>
+				<span class="collapse-sidebar-arrow"></span>
+			</a>
 			<div class="wp-full-overlay-sidebar">
 				<div class="wp-full-overlay-header"></div>
 				<div class="install-theme-info"></div>
+				<div class="wp-full-overlay-footer"></div>
 			</div>
 			<div class="wp-full-overlay-main"></div>
 		</div>
diff --git a/wp-includes/class-wp-customize.php b/wp-includes/class-wp-customize.php
index 0adff4d133..d561d293bd 100644
--- a/wp-includes/class-wp-customize.php
+++ b/wp-includes/class-wp-customize.php
@@ -304,7 +304,10 @@ final class WP_Customize {
 		<div id="customize-container" class="wp-full-overlay">
 			<input type="hidden" class="admin-url" value="<?php echo esc_url( admin_url( 'admin.php' ) ); ?>" />
 			<a href="#" class="close-full-overlay"><?php printf( __( '&larr; Return to %s' ), get_admin_page_title() ); ?></a>
-			<a href="#" class="collapse-sidebar button-secondary" title="<?php esc_attr_e('Collapse Sidebar'); ?>"><span></span></a>
+			<a href="#" class="collapse-sidebar button-secondary" title="<?php esc_attr_e('Collapse Sidebar'); ?>">
+				<span class="collapse-sidebar-label"><?php _e('Collapse'); ?></span>
+				<span class="collapse-sidebar-arrow"></span>
+			</a>
 		</div>
 		<?php
 	}