instead of
image: postgres:16-alpine
use
image: pgautoupgrade/pgautoupgrade:16-alpine
Then all the upgrade instructions of backup->update->import backups
go away and all you need to do is restart the docker container. (still keep backups though!)
Reference: https://github.com/LemmyNet/lemmy/pull/4892/files
Since that pull request was merged, this will simplify future updates like 0.19.6 or 0.20.0
Yeah postgres updates should not be done in place, and especially not without a proper backup.