Every time I install the ProtonPass Firefox extension I have to remember to set a lock pin, otherwise the extension remains vulnerable.
Sometimes the extension updates itself, and even if it forces me to log in again (which is OK) the pin is lost, so I have to remember to set a pin again or be vulnerable.

I understand the pin is local to that extension, so my proposal is to follow what other password managers does, which is to lock with the password account if no pin has been set.
In that scenario, it would be a little bit more friction if I forgot to set a pin, but way better than being vulnerable.