Using Zeta 1.0-13 and Quark 4.0-436 on Forge 47.1.3, when setting the keybind for Quark's "Back" function to a mouse button (I tested Mouse 4 and 5), it immediately closes the keybind screen. When going back into that screen you can see the pressed key was accepted, but it also immediately executed said "back" function, even though the button press should have been for assigning the keybind. (This didn't seem to happen with keyboard keys,only with mouse buttons.)

Expected behavior:
Pressing a key or button to bind it to a UI-related function should not execute that functionality until the key/button press that established the binding has ended with that key/button being released and the key/button is pressed again.

Context:
I was testing whether a peculiar 1.18 Quark behavior was still present that was reported in the Discord. Someone unbound the "Back" function and suddenly had their / key cause the "back" behavior. I couldn't confirm that for 1.20.1 using any keyboard keys, but then again it might be specific to a particular keyboard layout or operating system. (Linux Mint with German layout here, for reference.)