There is no point in showing the tab on file pages which don’t exist locally, like https://www.mediawiki.org/wiki/File:Abcdefg.png. It should be hidden, just like on files which come from Commons (e.g. https://www.mediawiki.org/wiki/File:Example.svg).
Acceptance Criteria
- A file page that does not contain a file does not receive a "move to commons" link.