https://bugs.freedesktop.org/show_bug.cgi?id=110214
--- Comment #76 from Michel Dänzer michel@daenzer.net --- (In reply to Diego Viola from comment #24)
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
Can you double-check this with Xephyr, taking everything we've learned since then into account, and if the same commit is identified again, file a new report about it?