https://bugs.freedesktop.org/show_bug.cgi?id=110214
--- Comment #24 from Diego Viola diego.viola@gmail.com --- I've bisected the issue with the GTK elements sometimes disappearing, and the commit that causes the issue is this one:
1b25d340b791ad8350bdfb27f1a91ac79fa17748 is the first bad commit
Sadly my xterm is still affected but I can confirm this commit causes the issue with the GTK windows, going back to the previous commit fixes the issue with the invisible element in GIMP.
Does it shed any light for my original issue (invisible output in xterm)?
Sorry for mixing things up.