Back on trialing Calibre 5.
I just downloaded 5.5 and updated GetFileName to 0.1.0. I also checked that GetFileName's preference dialog works - and it still has the same column settings for Filename, FolderPath and FileDate I had setup in Calibre 4 .
Then I imported a book (a PDF) - but none of the three metadata fields are populated.
Is the GetFileName plugin meant to work with Calibre 5?