This will break your deployment!
You need to add new lines to /config/production.yaml as shown here:
https://github.com/Chocobozzz/PeerTube/blob/v5.0.0/config/production.yaml.example#L14
https://github.com/Chocobozzz/PeerTube/blob/v5.0.0/config/production.yaml.example#L153

you can do that from the host as the file is inside a volume. It should be in /var/lib/docker/volumes/<peertube stack name>_app-config/_data/production.yaml on your host machine. It's important to save the secret that you're putting in the file somewhere else, as the container has write access to the file, and it's possible it could overwrite it, causing the secret to disappear. We don't know what happens to your data if you lose that secret.

You'll also have to run a migration as described in https://github.com/Chocobozzz/PeerTube/releases/tag/v5.0.0

abra app run <app name> app bash -u peertube
and when inside the container:
node dist/scripts/migrations/peertube-5.0.js

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