pg_upgrade(?) not cleaning up old extensions

Hello,

I have a (test) database that has been upgraded several times from 9.4 to 13 using pg_upgrade.

I have noticed that when I look at pg_available_extensions many extensions are listed with multiple versions even though only the latest one is actually used.

I did "alter extension ... update" for those that are installed in the database after running pg_upgrade. But the multiple versions even show up for extensions that are not installed.

After I did a dump & restore of the database in question, this list was cleaned and only the most recent version of the extensions were shown.

This is not a big deal, but I am curious neverthless:

Did I have another choice to cleanup that apart from doing the dump & restore?

Running "drop extension" obviously doesn't work for those that aren't installed.

Thomas