Issues dragging screen in browser based game

Issues with both Chrome and Opera dragging the screen in browser based game since latest update. The game is called Smallworlds. Several users have reported this issue on game forums and the only browser that still works would be firefox.

Dragging the screen is sluggish, almost uncontrolled and freezes game play.

For me the issue started about 2 days ago on opera and 2-3 weeks ago on chrome.

Not sure where to post