Index: src/wp-admin/css/customize-controls.css
===================================================================
--- src/wp-admin/css/customize-controls.css	(revision 40667)
+++ src/wp-admin/css/customize-controls.css	(working copy)
@@ -710,6 +710,7 @@
 	padding-top: 7px;
 }
 
+/* Remove descender space. */
 .customize-control .thumbnail-image,
 .customize-control-header .current,
 .customize-control .wp-media-wrapper.wp-video {
@@ -716,6 +717,11 @@
 	line-height: 0;
 }
 
+/* Remove descender space. */
+.customize-control .favicon-preview .browser-preview {
+	vertical-align: top;
+}
+
 .customize-control .thumbnail-image img {
 	cursor: pointer;
 }
Index: src/wp-includes/customize/class-wp-customize-header-image-control.php
===================================================================
--- src/wp-includes/customize/class-wp-customize-header-image-control.php	(revision 40667)
+++ src/wp-includes/customize/class-wp-customize-header-image-control.php	(working copy)
@@ -204,8 +204,7 @@
 			<div class="actions">
 				<?php if ( current_user_can( 'upload_files' ) ): ?>
 				<button type="button"<?php echo $visibility; ?> class="button remove" aria-label="<?php esc_attr_e( 'Hide header image' ); ?>"><?php _e( 'Hide image' ); ?></button>
-				<button type="button" class="button new" id="header_image-button"  aria-label="<?php esc_attr_e( 'Add new header image' ); ?>"><?php _e( 'Add new image' ); ?></button>
-				<div style="clear:both"></div>
+				<button type="button" class="button new" id="header_image-button" aria-label="<?php esc_attr_e( 'Add new header image' ); ?>"><?php _e( 'Add new image' ); ?></button>
 				<?php endif; ?>
 			</div>
 			<div class="choices">
Index: src/wp-includes/customize/class-wp-customize-media-control.php
===================================================================
--- src/wp-includes/customize/class-wp-customize-media-control.php	(revision 40667)
+++ src/wp-includes/customize/class-wp-customize-media-control.php	(working copy)
@@ -192,7 +192,6 @@
 					<# if ( data.canUpload ) { #>
 					<button type="button" class="button remove-button">{{ data.button_labels.remove }}</button>
 					<button type="button" class="button upload-button control-focus" id="{{ data.settings['default'] }}-button">{{ data.button_labels.change }}</button>
-					<div style="clear:both"></div>
 					<# } #>
 				</div>
 			</div>
@@ -208,7 +207,6 @@
 					<# if ( data.canUpload ) { #>
 					<button type="button" class="button upload-button" id="{{ data.settings['default'] }}-button">{{ data.button_labels.select }}</button>
 					<# } #>
-					<div style="clear:both"></div>
 				</div>
 			</div>
 		<# } #>
Index: src/wp-includes/customize/class-wp-customize-site-icon-control.php
===================================================================
--- src/wp-includes/customize/class-wp-customize-site-icon-control.php	(revision 40667)
+++ src/wp-includes/customize/class-wp-customize-site-icon-control.php	(working copy)
@@ -62,7 +62,7 @@
 		<# if ( data.attachment && data.attachment.id ) { #>
 			<div class="attachment-media-view">
 				<# if ( data.attachment.sizes ) { #>
-					<div class="site-icon-preview">
+					<div class="site-icon-preview wp-clearfix">
 						<div class="favicon-preview">
 							<img src="<?php echo esc_url( admin_url( 'images/' . ( is_rtl() ? 'browser-rtl.png' : 'browser.png' ) ) ); ?>" class="browser-preview" width="182" alt="" />
 
@@ -78,7 +78,6 @@
 					<# if ( data.canUpload ) { #>
 						<button type="button" class="button remove-button"><?php echo $this->button_labels['remove']; ?></button>
 						<button type="button" class="button upload-button" id="{{ data.settings['default'] }}-button"><?php echo $this->button_labels['change']; ?></button>
-						<div style="clear:both"></div>
 					<# } #>
 				</div>
 			</div>
@@ -94,7 +93,6 @@
 					<# if ( data.canUpload ) { #>
 						<button type="button" class="button upload-button" id="{{ data.settings['default'] }}-button"><?php echo $this->button_labels['select']; ?></button>
 					<# } #>
-					<div style="clear:both"></div>
 				</div>
 			</div>
 		<# } #>