that&#x27;s a load of work for some fake internet point.<p>and no on some browser the scrollbars consume layout space and on some they don&#x27;t. (remember to add the ios&#x2F;safari monstrosities into the mix)<p>heck, just open this <a href="http:&#x2F;&#x2F;www.matanich.com&#x2F;test&#x2F;viewport-width&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.matanich.com&#x2F;test&#x2F;viewport-width&#x2F;</a> on edge&#x2F;ie11&#x2F;chrome and see yourself how reliable clientWidth is (especially test edge fullscreen vs edge windowed but fullscreen it will blow your mind)