After months of my 64GB HA OS getting closer to full with no solution from other posts, I had the random idea to check the Images in Portainer (I only have it for one small container that doesn’t exist as add-on, PlexTraktSync), and there were tens of unused images…
Even from the same add-on that I no longer have, like the official Plex. There were like 25 of it, each 665MB.
After deleting them, all carefully reviewing not only that they were unused, but that it’s something I don’t use (eg. stopped add-ons will say Unused too), I have recovered 25GB and now running at 35% used storage…