diff --git a/includes/OutputPage.php b/includes/OutputPage.php
index e19ac7da0fd..6f1831214bf 100644
--- a/includes/OutputPage.php
+++ b/includes/OutputPage.php
@@ -1894,6 +1894,14 @@ class OutputPage {
 	 */
 	public function addStyle( $style, $media='', $condition='', $dir='' ) {
 		$options = array();
+		// In Opera, fullscreen mode is treated as projection mode, and it causes
+		// styles set for screen to not be loaded - thus breaking the page -  so
+		// we can just append projection to the media attribute when it's screen
+		// so the browser is happy and - with no side-effects on other browsers.
+		// Also - even though we expect the media type to be lowercase, but here
+		// we force it to lowercase to be safe.
+		if ( strtolower( $media ) == 'screen' )
+			$media .= ',projection';
 		if( $media )
 			$options['media'] = $media;
 		if( $condition )