I just noted that ANY .duplicacy folder is not backed up. I would consider that a bug. I was using a .duplicacy folder to store my filter files, etc. I most definitely did not expect that not to be backed up. If it wasn’t for my “old” backup program backing it up it would have been lost.
I have duplicacy installed in “ProgramData”, so I think this is definitely unexpected behavior. But I think it should even backup it’s own folder. Adding a filter of the form “+.duplicacy/” doesn’t seem to change anything.