Sorry, I already had one idea today that I posted earlier, but here is another.
There are times when I open 2 QB64 Windows side by side so that I can compare some existing code from one Window and start making modifications to a copy of the file in the other window. However, there are times where I accidentally started doing code updates in the wrong window. It would be great if there was a toggle to make one window a view only window. That way, if I started trying to type into the wrong window and saw that nothing was happening (or maybe even a beep could play), I would have instant visual feedback that this is my view only window.