Index: src/wp-admin/css/list-tables.css
===================================================================
--- src/wp-admin/css/list-tables.css	(revision 32720)
+++ src/wp-admin/css/list-tables.css	(working copy)
@@ -423,6 +423,55 @@
 	content: '\f140';
 }
 
+.wp-list-table .toggle-row {
+	position: absolute;
+	right: 8px;
+	top: 10px;
+	display: none;
+	padding: 0;
+	width: 40px;
+	height: 40px;
+	border: none;
+	background: transparent;
+}
+
+.wp-list-table .toggle-row:hover {
+	cursor: pointer;
+}
+
+.wp-list-table .toggle-row:focus {
+	color: #124964;
+    -webkit-box-shadow:
+    	0 0 0 1px #5b9dd9,
+		0 0 2px 1px rgba(30, 140, 190, .8);
+    box-shadow:
+    	0 0 0 1px #5b9dd9,
+		0 0 2px 1px rgba(30, 140, 190, .8);
+}
+
+.ie8 .wp-list-table .toggle-row:focus {
+	outline: #5b9dd9 solid 1px;
+}
+
+.wp-list-table .toggle-row:before {
+	position: absolute;
+	top: 0;
+	left: 10px;
+	display: block;
+	padding: 0;
+	color: #666;
+	content: '\f140';
+	font: normal 20px/1 'dashicons';
+	line-height: 10px;
+	-webkit-font-smoothing: antialiased;
+	-moz-osx-font-smoothing: grayscale;
+	speak: none;
+}
+
+.wp-list-table .is-expanded .toggle-row:before {
+	content: '\f142';
+}
+
 tr.wp-locked .locked-indicator {
 	margin-left: 6px;
 	height: 20px;
@@ -1644,34 +1693,56 @@
 		font-size: 14px;
 	}
 
-	/* Columns to hide */
-	.fixed .column-date,
-	.fixed .column-author,
-	.column-categories,
-	.column-tags,
-	.tags .column-description,
-	.media .column-parent,
-	.media .column-comments,
-	.users .column-email,
-	.users .column-name,
-	.sites .column-registered,
-	.sites .column-users {
+	.wp-list-table th:not(.column-primary),
+	.wp-list-table th:not(.column-primary),
+	.wp-list-table tr:not(.inline-edit-row) td:not(.column-primary) {
 		display: none;
 	}
 
-	.fixed .column-comment .comment-author {
+	/* Checkboxes need to show */
+	.wp-list-table th.check-column {
+		display: table-cell;
+		width: 35px;
+	}
+
+	.wp-list-table .toggle-row {
 		display: block;
 	}
 
-	/* Posts */
-	.column-title {
-		width: 85%;
+	.wp-list-table tr:not(.inline-edit-row) td {
+		position: relative;
+		clear: both;
+		display: block;
+		width: auto !important; /* needs to override some columns that are more specifically targeted */
 	}
 
-	.fixed .column-comments, .widefat .check-column {
-		width: 35px
+	.wp-list-table td.column-primary {
+		padding-right: 50px; /* space for toggle button */
 	}
 
+	.wp-list-table tr:not(.inline-edit-row) td:not(.column-primary) {
+		padding: 3px 8px 3px 35% !important; /* space for the label */
+	}
+
+	.wp-list-table tr:not(.inline-edit-row) td:not(.column-primary)::before {
+		position: absolute;
+		left: 10px; /* match padding of regular table cell */
+		display: block;
+		overflow: hidden;
+		width: 32%; /* leave a little space for a gutter */
+		content: attr(data-colname);
+		white-space: nowrap;
+		text-overflow: ellipsis;
+	}
+
+	.wp-list-table .is-expanded td {
+		display: block !important;
+	}
+
+	.fixed .column-comment .comment-author {
+		display: block;
+	}
+
 	.widefat thead .check-column, .widefat tfoot .check-column {
 		padding: 10px 0 10px;
 	}
@@ -1907,7 +1978,7 @@
 	}
 
 	.widefat tbody th.check-column input[type="checkbox"] {
-		margin-top: -3px;
+		margin-top: -4px;
 		margin-left: 8px;
 	}
 
Index: src/wp-admin/includes/class-wp-list-table.php
===================================================================
--- src/wp-admin/includes/class-wp-list-table.php	(revision 32722)
+++ src/wp-admin/includes/class-wp-list-table.php	(working copy)
@@ -497,6 +497,8 @@
 		}
 		$out .= '</div>';
 
+		$out .= '<button type="button" class="toggle-row"><span class="screen-reader-text">Show more details</span></button>';
+
 		return $out;
 	}
 
@@ -921,7 +923,7 @@
 	 * @param bool $with_id Whether to set the id attribute or not
 	 */
 	public function print_column_headers( $with_id = true ) {
-		list( $columns, $hidden, $sortable ) = $this->get_column_info();
+		list( $columns, $hidden, $sortable, $primary ) = $this->get_column_info();
 
 		$current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );
 		$current_url = remove_query_arg( 'paged', $current_url );
@@ -957,6 +959,10 @@
 			elseif ( in_array( $column_key, array( 'posts', 'comments', 'links' ) ) )
 				$class[] = 'num';
 
+			if ( $column_key === $primary ) {
+				$class[] = 'column-primary';
+			}
+
 			if ( isset( $sortable[$column_key] ) ) {
 				list( $orderby, $desc_first ) = $sortable[$column_key];
 
Index: src/wp-admin/includes/class-wp-posts-list-table.php
===================================================================
--- src/wp-admin/includes/class-wp-posts-list-table.php	(revision 32721)
+++ src/wp-admin/includes/class-wp-posts-list-table.php	(working copy)
@@ -727,7 +727,14 @@
 				$style = ' style="display:none;"';
 			}
 
-			$attributes = "class='$classes'$style";
+			// Comments is a special case, as its column display name contains HTML
+ 			if ( 'comments' === $column_name ) {
+ 				$data = ' data-colname="' . esc_attr__( 'Comments' ) . '"';
+ 			} else {
+ 				$data = ' data-colname="' . esc_attr( $column_display_name ) . '"';
+ 			}
+  
+ 			$attributes = "class='$classes'$style$data";
 
 			if ( 'cb' === $column_name ) {
 				?>
Index: src/wp-admin/js/common.js
===================================================================
--- src/wp-admin/js/common.js	(revision 32720)
+++ src/wp-admin/js/common.js	(working copy)
@@ -480,6 +480,11 @@
 		}
 	}, 'td.has-row-actions' );
 
+	// Toggle list table rows on small screens
+	$( 'tbody' ).on( 'click', '.toggle-row', function() {
+		$( this ).closest( 'tr' ).toggleClass( 'is-expanded' );
+	});
+
 	$('#default-password-nag-no').click( function() {
 		setUserSetting('default_password_nag', 'hide');
 		$('div.default-password-nag').hide();