Firefox, Linux Mint.
Viewing post in Gold Digger (Simple Idle Game) comments
Okay, if you are running Firefox you may have to update it, they explain why here: https://itch.io/t/2025776/experimental-sharedarraybuffer-support
Also Godot 4 does not support WebGL 1 (as far as I know it only supports WebGL 2), so that could also be the issue.