PR# 19575 EiffelStudio edit warning for locked library class

I have started to use additional windows to study library classes next to other code (rather than switching between tabs, I can make windows side-by side on screen).

Problem: opening a file into the editor will trigger a warning that it is already in use in a different editor. With non-editable library classes this is non-sensical.

Please don't give the hint for locked library class files (otherwise considered helpful).

open a library class in the editor for viewing, open a separate New Window, attempt to open same class.

Attachments for problem report #19575