Every application's file open/save dialogue asks for "Keystroke Receiving" permission Is this a normal thing or I have some kind of plugins or applications which makes my requesters require this permission?
I'm not sure why every application would want this. I have heard that apps using JavaFX trigger this permission, even though they don't explicitly want or need it. 

It's therefore possible that it is an unintended effect rather than an actual case of apps needing or wanting to monitor the keyboard input.

Probably best to deny and then allow if problems occur with the specific apps involved.