Index: src/wp-admin/css/press-this.css
===================================================================
--- src/wp-admin/css/press-this.css	(revision 31544)
+++ src/wp-admin/css/press-this.css	(working copy)
@@ -217,9 +217,9 @@
 }
 
 fieldset {
-	border: 1px solid #c0c0c0;
-	margin: 0 2px;
-	padding: 0.35em 0.625em 0.75em;
+	border: 0;
+	margin: 0;
+	padding: 0;
 }
 
 legend {
Index: src/wp-admin/includes/class-wp-press-this.php
===================================================================
--- src/wp-admin/includes/class-wp-press-this.php	(revision 31544)
+++ src/wp-admin/includes/class-wp-press-this.php	(working copy)
@@ -133,11 +133,11 @@
 		if ( empty( $_POST['post_ID'] ) || ! $post_id = (int) $_POST['post_ID'] ) {
 			wp_send_json_error( array( 'errorMessage' => __( 'Missing post ID.' ) ) );
 		}
-	
+
 		if ( ! current_user_can( 'edit_post', $post_id ) ) {
 			wp_send_json_error( array( 'errorMessage' => __( 'Cheatin’ uh?' ) ) );
 		}
-	
+
 		$post = array(
 			'ID'            => $post_id,
 			'post_title'    => ( ! empty( $_POST['title'] ) ) ? sanitize_text_field( trim( $_POST['title'] ) ) : '',
@@ -148,7 +148,7 @@
 			'tax_input'     => ( ! empty( $_POST['tax_input'] ) ) ? $_POST['tax_input'] : array(),
 			'post_category' => ( ! empty( $_POST['post_category'] ) ) ? $_POST['post_category'] : array(),
 		);
-	
+
 		if ( ! empty( $_POST['post_status'] ) && 'publish' === $_POST['post_status'] ) {
 			if ( current_user_can( 'publish_posts' ) ) {
 				$post['post_status'] = 'publish';
@@ -164,7 +164,7 @@
 		}
 
 		$updated = wp_update_post( $post, true );
-	
+
 		if ( is_wp_error( $updated ) || intval( $updated ) < 1 ) {
 			wp_send_json_error( array( 'errorMessage' => __( 'Error while saving the post. Please try again later.' ) ) );
 		} else {
@@ -192,7 +192,7 @@
 				/** This filter is documented in wp-admin/includes/class-wp-press-this.php */
 				$redirect = apply_filters( 'press_this_save_redirect', get_edit_post_link( $post_id, 'raw' ), $post_id, $post['post_status'] );
 			}
-	
+
 			wp_send_json_success( array( 'redirect' => $redirect ) );
 		}
 	}
@@ -537,6 +537,7 @@
 
 				?>
 				<div id="post-formats-select">
+				<fieldset><legend class="screen-reader-text"><?php _e( 'Post formats' ); ?></legend>
 					<input type="radio" name="post_format" class="post-format" id="post-format-0" value="0" <?php checked( $post_format, '0' ); ?> />
 					<label for="post-format-0" class="post-format-icon post-format-standard"><?php echo get_post_format_string( 'standard' ); ?></label>
 					<?php
@@ -550,6 +551,7 @@
 						<?php
 					 }
 					 ?>
+				</fieldset>
 				</div>
 				<?php
 			}
@@ -569,8 +571,8 @@
 
 		if ( current_user_can( $taxonomy->cap->edit_terms ) ) {
 			?>
-			<button type="button" class="add-cat-toggle button-subtle">
-				<span class="dashicons dashicons-plus"></span>
+			<button type="button" class="add-cat-toggle button-subtle" aria-expanded="false">
+				<span class="dashicons dashicons-plus"></span><span class="screen-reader-text"><?php _e( 'Toggle add category' ); ?></span>
 			</button>
 			<div class="add-category is-hidden">
 				<label class="screen-reader-text" for="new-category"><?php echo $taxonomy->labels->add_new_item; ?></label>
@@ -592,12 +594,12 @@
 			</div>
 		<?php } ?>
 		<div class="categories-search-wrapper">
-			<input id="categories-search" type="search" class="categories-search" placeholder="<?php esc_attr_e( 'Search categories' ) ?>">
+			<input id="categories-search" type="search" class="categories-search" placeholder="<?php esc_attr_e( 'Search categories by name' ) ?>">
 			<label for="categories-search">
-				<span class="dashicons dashicons-search"></span>
+				<span class="dashicons dashicons-search"></span><span class="screen-reader-text"><?php _e( 'Search categories' ); ?></span>
 			</label>
 		</div>
-		<ul class="categories-select">
+		<ul class="categories-select" aria-label="<?php esc_attr_e( 'Categories' ); ?>">
 			<?php wp_terms_checklist( $post->ID, array( 'taxonomy' => 'category' ) ); ?>
 		</ul>
 		<?php
@@ -645,9 +647,7 @@
 		<?php
 		if ( $user_can_assign_terms ) {
 			?>
-			<p>
-				<a href="#titlediv" class="tagcloud-link" id="link-post_tag"><?php echo $taxonomy->labels->choose_from_most_used; ?></a>
-			</p>
+			<button type="button" class="button-reset button-link tagcloud-link" id="link-post_tag"><?php echo $taxonomy->labels->choose_from_most_used; ?></button>
 			<?php
 		}
 	}
@@ -756,6 +756,7 @@
 
 	<div id="scanbar" class="scan">
 		<form method="GET">
+			<label for="url-scan" class="screen-reader-text"><?php _e( 'Scan site for content' ); ?></label>
 			<input type="url" name="u" id="url-scan" class="scan-url" value="" placeholder="<?php esc_attr_e( 'Enter a URL to scan' ) ?>" />
 			<input type="submit" name="url-scan-submit" id="url-scan-submit" class="scan-submit" value="<?php esc_attr_e( 'Scan' ) ?>" />
 		</form>
@@ -841,20 +842,18 @@
 
 			<?php if ( $supports_formats ) : ?>
 				<div class="setting-modal is-off-screen is-hidden">
-					<button type="button" class="button-reset modal-close">
-						<span class="dashicons dashicons-arrow-left-alt2"></span><span class="setting-title"><?php _e( 'Post format' ); ?></span>
-					</button>
+					<button type="button" class="button-reset modal-close"><span class="dashicons dashicons-arrow-left-alt2"></span><span class="setting-title" aria-hidden="true"><?php _e( 'Post format' ); ?></span><span class="screen-reader-text"><?php _e( 'Back to post options' ) ?></span></button>
 					<?php $this->post_formats_html( $post ); ?>
 				</div>
 			<?php endif; ?>
 
 			<div class="setting-modal is-off-screen is-hidden">
-				<button type="button" class="button-reset modal-close"><span class="dashicons dashicons-arrow-left-alt2"></span><span class="setting-title"><?php _e( 'Categories' ); ?></span></button>
+				<button type="button" class="button-reset modal-close"><span class="dashicons dashicons-arrow-left-alt2"></span><span class="setting-title" aria-hidden="true"><?php _e( 'Categories' ); ?></span><span class="screen-reader-text"><?php _e( 'Back to post options' ) ?></span></button>
 				<?php $this->categories_html( $post ); ?>
 			</div>
 
 			<div class="setting-modal tags is-off-screen is-hidden">
-				<button type="button" class="button-reset modal-close"><span class="dashicons dashicons-arrow-left-alt2"></span><span class="setting-title"><?php _e( 'Tags' ); ?></span></button>
+				<button type="button" class="button-reset modal-close"><span class="dashicons dashicons-arrow-left-alt2"></span><span class="setting-title" aria-hidden="true"><?php _e( 'Tags' ); ?></span><span class="screen-reader-text"><?php _e( 'Back to post options' ) ?></span></button>
 				<?php $this->tags_html( $post ); ?>
 			</div>
 		</div><!-- .options-panel -->
Index: src/wp-admin/js/press-this.js
===================================================================
--- src/wp-admin/js/press-this.js	(revision 31544)
+++ src/wp-admin/js/press-this.js	(working copy)
@@ -810,7 +810,7 @@
 				$targetSettingModal
 					.removeClass( isOffScreen + ' ' + isHidden )
 					.one( transitionEndEvent, function() {
-						$( this ).find( $modalClose ).focus();
+						$( this ).find( '.modal-close' ).focus();
 					} );
 			} );
 
@@ -827,6 +827,7 @@
 					.addClass( isOffScreen )
 					.one( transitionEndEvent, function() {
 						$( this ).addClass( isHidden );
+						$postOption.eq( index - 1 ).focus();
 					} );
 
 				// For browser that don't support transitionend.
@@ -833,10 +834,9 @@
 				if ( ! transitionEndEvent ) {
 					setTimeout( function() {
 						$targetSettingModal.addClass( isHidden );
+						$postOption.eq( index - 1 ).focus();
 					}, 350 );
 				}
-
-				$postOption.eq( index - 1 ).focus();
 			} );
 		}
 
@@ -964,6 +964,7 @@
 
 			$( 'button.add-cat-toggle' ).on( 'click.press-this', function() {
 				$( this ).toggleClass( 'is-toggled' );
+				$( this ).attr( 'aria-expanded', $( this ).attr( 'aria-expanded' ) === 'false' ? 'true' : 'false' );
 				$( '.setting-modal .add-category' ).toggleClass( 'is-hidden' );
 				$( '.categories-search-wrapper' ).toggleClass( 'is-hidden' );
 			} );
Index: src/wp-admin/js/tags-box.js
===================================================================
--- src/wp-admin/js/tags-box.js	(revision 31544)
+++ src/wp-admin/js/tags-box.js	(working copy)
@@ -18,7 +18,7 @@
 
 		return out;
 	};
-	
+
 	tagBox = {
 		clean : function(tags) {
 			var comma = window.tagsBoxL10n.tagDelimiter;
@@ -193,7 +193,7 @@
 			});
 
 			// tag cloud
-			$('a.tagcloud-link').click(function(){
+			$('.tagcloud-link').click(function(){
 				tagBox.get( $(this).attr('id') );
 				$(this).unbind().click(function(){
 					$(this).siblings('.the-tagcloud').toggle();
Index: src/wp-admin/tools.php
===================================================================
--- src/wp-admin/tools.php	(revision 31544)
+++ src/wp-admin/tools.php	(working copy)
@@ -57,7 +57,7 @@
 			</button>
 		</p>
 
-		<div class="hidden js-pressthis-code-wrap">
+		<div class="hidden js-pressthis-code-wrap" id="pressthis-code-wrap">
 			<p id="pressthis-code-desc">
 				<?php _e( 'If you can\'t drag it to your bookmarks, copy the following code and create new bookmark. Paste the code into the new bookmark\'s URL field.' ) ?>
 			</p>