#394 screen refresh problems with fvwm window manager

[Ott Toomet]

ubuntu 14.04, fvwm: xdvik does not display correct picture without additional refreshing (see attachment, apparently this is not visible in screenshot). I can get the picture correct by pressing arrow keys, mouse buttons, changing between expert mode etc, but the picture is carbled again when the window becomes invisible and visible again.

This affects both version 22.86 and 22.87. I have not encountered this problem when using unity instead of fvwm.