I have tried this on my desktop computer and laptop. Both experience the same problem. Also, both the itch.io version (with sandboxing on or off) and standalone version are affected. I am using elementary OS 5.0 Juno. It is a Linux distribution based on Ubuntu 18.04.
CPU: Intel i5-4460
GPU: AMD Radeon R9 290
GPU drivers: Mesa from Padoka Stable PPA, currently 18.2.4
Laptop, Packard Bell EasyNote TE69KB
CPU: AMD E3-2800
GPU: AMD Radeon HD 8280
GPU drivers: Default Mesa, currently 18.0.5
If you need any further information, let me know.