I have several sources that show 1 citation in the Sources list but show zero used on the Edit Source screen. When I try to delete them, I get “This source has existing citations. Are you sure you want to delete it?” Is it safe to delete these sources?
Yes, but do a Backup first. Then, it can be “referred back to” if the need arises.
I have a suspicion that your Source actually is used somewhere
Under the circumstances you describe, I would probably delete the Citation first, and then delete the Source. Doing it that order should make sure that I’m not deleting a Source which has a Citation which is in use.
Before deleting the Citation, be very sure that it’s own use count is zero. So if you are in the main Sources tab, highlight the Source in question. If its use count is not zero, highlight its use count to slide in its list of Citations. And look at the use counts for the Citations. If a Citation’s use count is zero, it’s safe to delete at that point. Then if the Source’s count is zero, it’s safe delete at that point. If a Citation’s use count is not zero, you can click on the use count to slide in a panel to see where it is being used.
Thank you for the advice. It was helpful to double check as you suggested.