here is a script example that you could use to tidy up files and the trashbin… ALL files retention - is it possible ? - #2 by scubamuc you could also simply purge the trashbin regularly, like once a day with a cronjob:
create a root cronjob to run occ trashbin:cleanup --all-users regularly, or run the script in a shell on demand.
#!/bin/bash
## force purge trashbin per user and groupfolders
echo "PURGE TRASHBIN";
sudo occ trashbin:cleanup --all-users ;
sudo occ groupfolders:trashbin:cleanup -f ;
exit