This was an issue before Loenn 1.0, where I would open up Loenn to map, then leave it open for a few hours while I did something else, and then when I came back it would take 10 seconds for any button press to register.
When Loenn 1.0 released, however, the issue got worse, and now I'm having to restart the program within the same session because it starts taking too long to register anything.
Note that this is only for button presses and opening menus, actually placing down things functions at the same speed all the time.
I am on EndeavourOS Linux.