The first time I've started the game on Linux (latest Manjaro), I've encountered the same problem, but closing and re-opening the game fixed it (or maybe it's just random). There were no error messages on the terminal.
humm, nice to know Fodi, we started it a several times in linux and this does not happen... We have a guess about redering order or Z order in our GUI... Anyway is knowledge to think about in the next projects
