(In reply to Michel Dänzer from comment #1)
> Please attach the corresponding Xorg log file and output of glxinfo and
> dmesg.

Done.

> 
> I can't seem to reproduce this, and I'm not sure what exactly "parts of the
> scrollback buffer disappear" means. Maybe you can make a screencast or
> screenshots demonstrating the problem?

By that I mean the actual text/output disappears after I do shift+page up, but
it doesn't if I scroll with the mouse wheel or if I use the scrollbar.

I've attached a video demonstrating the issue, please let me know if you need
more info.

Thanks.