Adobe reader messes up the screen
 

Does anyone else have this kind of nuisance with Adobe Reader?
It was worse when "Show thumbnails on tab hover" was selected - then there were thumbnails all over, now just the file names.

Attachment 17910

Any idea how to get rid of those?

Those look like remnants, areas of the screen that are not getting updated or redrawn. It's symptomatic of resource starvation, your processor or ram memory is getting maxed out and to keep the ball in the air your kernel is looking at the redraw call and intermittently saying... " Eh, screw it".
If you run an htop, you'll probably see you are deep, deep, deep into swap (we've all been there, it's a bad place).
Try shutting down some browser windows (browsers suck up dynamic memory, chrome is the worst but firefox isn't much better). You could also minimize the browser or move it to a desktop not visible on the display (you're drawing a lot of layers here.).
Not to say any of that would help, but it's worth trying before giving up on Adobe Reader (which is no slouch at consuming precious resources either) and switching to Evince.

Thanks.
I'll check what I can do. The firefox pdf-viewer just doesn't display all the stuff. Especially pictures tend to be missing.

I probably am short of memory - the machine is StinkBad T42.