--- a/layout/style/res/ua.css
+++ b/layout/style/res/ua.css
@@ -287,17 +287,17 @@
   width: 100% !important;
   height: 100% !important;
   margin: 0 !important;
   min-width: 0 !important;
   max-width: none !important;
   min-height: 0 !important;
   max-height: none !important;
   box-sizing: border-box !important;
-  object-fit: contain !important;
+  object-fit: contain;
   transform: none !important;
 }
 
 /* Selectors here should match the check in
  * nsViewportFrame.cpp:ShouldInTopLayerForFullscreen() */
 *|*:fullscreen:not(:root):not(:-moz-browser-frame) {
   -moz-top-layer: top !important;
 }