I am looking for a word describing a software package that has not been updated for a long time, and although it still works with new versions of the underlying software, bugs have not been fixed for years, and no new features have been added.
I found this similar question, however, none of the words from the answer really seem to match, because the software package still exists and works, but just has not been updated in a long time. So it was not retired, or replaced, or terminated, or deprecated, or sunsetted.
"Unsupported" would somewhat match, but this essentially applied to a huge number of similar packages which are typically not officially supported. "Abandoned" sounds a bit harsh to me, as I would use the word in a document that the original author of the package might get to see at some point.
I was thinking about something like "obsolete" or "outdated", but this sort of seems to imply that there exists something newer, or better replacing the old package, which is not the case.