restore clipboard setup?
@datapythonista do you recall why these lines were removed in https://github.com/pandas-dev/pandas/pull/28531/files?
We call xvfb with the command directly in https://github.com/pandas-dev/pandas/blob/master/ci/run_tests.sh#L33, we shouldn't need that. Is that causing any trouble? OK, thanks. No idea if it's causing issues. I'll rerun the travis job that has been failing a few times to see if it's present on this branch. Dunno if this is related, but I do see

> QXcbClipboard::setMimeData: Cannot set X11 selection owner

In the output log. I assume that the tests are run under the same `user` as everything else though, so not sure what that actually means. Things passed with https://github.com/pandas-dev/pandas/pull/29695/commits/a93b9d8074a768f79b6da45eb4859a4efac421ed. Going to restart the problematic job a few times.

1 / 1 I've been going through logs. The "Cannot set X11 selection owner" warning seems relevant. It's been present in all the failed builds, and absent in all the successful ones. I found this post very useful when dealing with clipboard test errors in the past, and trying to understand how things work: https://www.uninformativ.de/blog/postings/2017-04-02/0/POSTING-en.html

Still very confused, and I don't know how to fix that error yet, but I think the article is worth reading. I'm wondering if we're copying and pasting too fast, and if a short sleep in between would get rid of the error... I have one theory to try out before then. I'm worried about the module-level `to_clipboard` we attempt. That would be executed on import. Putting that behind a fixture. With some luck #29712 may fix the problem. Some info here: http://elementalselenium.com/tips/38-headless

If that doesn't work, I'll probably focus on moving the db builds to GitHub actions, where I guess the X server is provided, we don't need `xvfb-run`, and I think the test won't fail. Thanks. Hopefully https://github.com/pandas-dev/pandas/pull/29712 fixes it.