Index: src/wp-includes/css/media-views.css
===================================================================
--- src/wp-includes/css/media-views.css	(revision 29519)
+++ src/wp-includes/css/media-views.css	(working copy)
@@ -442,6 +442,12 @@
 	margin: 0;
 }
 
+.sidebar-for-errors .attachment-details,
+.sidebar-for-errors .compat-item,
+.sidebar-for-errors .media-progress-bar,
+.sidebar-for-errors .upload-details {
+	display: none !important;
+}
 
 /**
  * Menu
Index: src/wp-includes/js/media-grid.js
===================================================================
--- src/wp-includes/js/media-grid.js	(revision 29519)
+++ src/wp-includes/js/media-grid.js	(working copy)
@@ -226,7 +226,7 @@
 		},
 
 		sidebarVisibility: function() {
-			this.browserView.$( '.media-sidebar' ).toggle( this.errors.length );
+			this.browserView.$( '.media-sidebar' ).toggle( this.errors.length > 0 );
 		},
 
 		bindDeferred: function() {
Index: src/wp-includes/js/media-views.js
===================================================================
--- src/wp-includes/js/media-views.js	(revision 29519)
+++ src/wp-includes/js/media-views.js	(working copy)
@@ -5771,6 +5771,10 @@
 
 			if ( ! this.options.sidebar || 'errors' === this.options.sidebar ) {
 				this.$el.addClass( 'hide-sidebar' );
+
+				if ( 'errors' === this.options.sidebar ) {
+					this.$el.addClass( 'sidebar-for-errors' );
+				}
 			}
 
 			this.collection.on( 'add remove reset', this.updateContent, this );