Hi!

After having played few rounds, and exiting the game by using Esc all
the way from the training screen, I got this:

,---
[…]
ap_Release_Play_List
ap_Release_Material_List
ap_Release
[xcb] Unknown request in queue while dequeuing
[xcb] Most likely this is a multi-threaded client and XInitThreads has not been called
[xcb] Aborting, sorry about that.
berusky2: ../../src/xcb_io.c:179: dequeue_pending_request: Assertion `!xcb_xlib_unknown_req_in_deq' failed.
Aborted
`---

(I'm filing some other bug reports for aborts and segfaults, separately
as they seem to be due to different root causes.)

Thanks,
Guillem