Hello everyone, I finally figured out how to fix this and i think it's a bug from Ubuntu because it's not only 0ad but goes same in other app too if you goes full screen.
Here the solution that works for me : https://askubuntu.com/questions/1433146/cursor-disappears-when-i-fullscreen-an-app-on-ubuntu-22-04
(and this method doesn't require to configure options in ~/.config/0ad/config/user.cfg)
Hello @nwtour , how can i access that file? I do that command on Terminal but i get "No such file or diretory".
Other information, I'm installing 0ad with snap
(Edit : i know it can be alt+enter and then cursor will appear, but it's not fullscreen)