Thanks for playing Capsule Wars!
I couldn't replicate the issue on my end, but nevertheless, I did a new build for Linux, redoing all my steps. Please try the new Linux executable and let me know if you still have issues.
You can join the Discord server or email me at busy.weasel.games@gmail.com for more questions. For bugs, please fill out the bug report form here.
Furthermore, I'd love to receive some feedback from you, it would help the game immensely!
Cheers,