What Cloudron fights you on for Plane: the single-container model.
It is probably better to just use Plane's Docker Compose and run it on its own little VPS.
Plane is not a monolithic app with a database bolted on. It is a distributed system with nine services, a message broker, and an object store. Cramming all of that into one container with supervisord is not how any of those components were designed to run. It works (Outline, Cal.com, Seafile, and Zoneminder have all been packaged this way), but the result is fragile in ways that a Docker Compose deployment is not. If the Celery worker crashes and supervisord restarts it, that is fine. If LavinMQ crashes and takes in-flight messages with it while the API is still accepting requests, you get silent failures that are hard to diagnose. The failure modes multiply with the number of co-located services.