diff --git a/core/misc/matchmedia.js b/core/misc/matchmedia.js
index 208a80a1a873efccf5e9e4090423f742ccdfe7c3..0dff91e077cc8f9cba2c8b2b2b22efb6e92b8585 100644
--- a/core/misc/matchmedia.js
+++ b/core/misc/matchmedia.js
@@ -75,7 +75,7 @@ window.matchMedia = window.matchMedia || (function (doc, window) {
           // Only execute the callback if the state has changed.
           var oldstate = mql.matches;
           mql.check();
-          if (oldstate != mql.matches) {
+          if (oldstate !== mql.matches) {
             debounced.call(mql, mql);
           }
         };