Comment 13 for bug 782855

I see the problem almost (but not quite) exclusively in browsers (both firefox and webkit-based, though I don't run chrome on that machine); never in simple apps like xterm or emacs, or in gimp.

Once it starts manifesting, its form will persist (e.g. if two lines of pixels are missing from lowercase b, then that will always be the case) through zooming, moving the browser window, reloading, opening new tabs, etc. However, if I quit firefox and restart it, I'll see a different pattern (e.g. it might be G and x mis-drawn now, rather than b) and that will persist through that run of firefox (but new letters might eventually start being affected as well). Once it starts, there's no chance of quitting and restarting to get a browser that has NO damaged letters; but sometimes I can get one where the bad letters are less common ones so I can still read pages for a while and can postpone rebooting.