I would like to suggest a new feature. I run two accounts. Same PC. Works great by the way! What I need is to be able to pass a key to the opposite window and not to the window I am currently in. White listing of course.

You could maybe just introduce a generalized filter. Where you can just filter keys overall.

Here is an example. My follow key is generally only on my alt. If I had this feature I could apply the same key to my main. This would allow me to switch windows and using the same key have the other follow.