Lately I see increasing numbers of video sites failing (using firefox and konqueror) without any indication of why. If I open the same link in Chromium I get a pop-up header saying the flash plugin is too old, with buttons to either update the plugin (which always fails using Linux) or to ignore the warning and play this video just this one time.

I can only watch one video after receiving this pop up, until I log out and back in to the desktop environment.

All other browsers just fail to play the video with no indication as to why the frame is blank. There's no runaway process when this happens, nothing seemingly related running that's not responding.

Is this html5 related? Bad coding? If so is there some way to provide helpful feedback?