Decompiler issues

Hello,

I've created a custom implementation of FileEditor, which works for the most part. The editor is for .class files. I have one issue though that I simply can't find the solution to:

I believe this only happens for classes that are already opened at startup. It's very inconsistent. Sometimes it happens, sometimes it doesn't.

Which class is responsible for displaying the above message?

Edit: One more thing I've noticed is that the selectNotify() method can get called up to three times upon opening a .class file in the non-default editor. Is that normal behavior? I feel like it's not.