@Sam-Fourie ,
It’s been suggested before, as in issue #17430. The developer stated explicitly:
It’s not my intesion to “lock” the document by using “Pin a document”. It’s just a way to make the documents grouped in front so users find them more easily. Checked with MS VC Studio, their behaviour is the same as Notepad++, and I think it’s the right behaviour.
It works the way the developer wants, and he has rejected the suggestion to make it work the way you want.
update: I’m not saying it’s not a good idea. Just that the developer (who is the final decision maker) is the one you’d need to convince. And, given that he’s already rejected the idea, you’d have to come up with something more than “I really want it” to convince him otherwise (and it would have to be posted in the issues tracker, presumably as a reply to the issue I linked, not in the user Community).