Been like this since the crap ral command was introduced Not found a way to resolve it, nothing via the view menu or on the screen resolution or zooooming in or out changes it. Works fine with firefox but doesn't display with chrome for me.
Worst for me is when taking the final turn in a winning game, ie finishing off an opponents last man. System continues to hang.
Communication with the server has timed out. Wait another 10 seconds? Just had this 5 times finishing off a game. Had to totally refresh the page (not the map) to finish.