Out of curiosity - why wouldn't we just use the Create timestamp or Date modified timestamp of the file on disk?

Out of curiosity - why wouldn't we just use the Create timestamp or Date modified timestamp of the file on disk?

I don't think those metadata are helpfull. UI will create and modify the file at the moment you drop the file in, or change label. Also create time of a file is usually not easy to pass to a different machine (especially to different OS).

With this PR I'm unable to drop new error reports onto the left panel to load new reports if I remove an entry and try to drag 'n' drop it in directly again. I then need to first close the UI and restart it. (it migth be that this behavior is similar as before)

That sounds like I've added a bug. Will look into it.

Also, if I drop in a file that's ALREADY in the UI then the UI appears to do nothing (no warning/error). I'd expect that if it should not add existing entries again, that instead it's best to highlight what matching entry already exists?

What if you'd drop 3 reports, 1 is new and 2 were already there, what should happen?

I can imagine that new entries are highlighted in some way, maybe? Probably not in this PR.

But maybe better is being able to load a file, again and again, as new entries?

That was actually a bug that you could do that. Each report has id, which is used for mapping in backend and also to store the report into file. Practically it is not possible to have 2 different reports with same id, until you manually modify them.