Portainer: Where are the Stack compose files saved?

Are you managing the same endpoint with the new Portainer instance? If not, then your old stacks will not be listed inside of Portainer as you haven't migrated them also. If you can see your stacks, but they are showing as limited this is because Portainer couldn't find the corresponding stack file and could possibly be due to how you have mounted your volume.

I can't give you instructions on how to migrate as we don't have any official instructions for this.

To answer your question: Inside the /data directory there is a directory called compose which is where the stack files are stored. Inside /compose, there will be directories labelled after the corresponding stackID in the Portainer database. You will have for example /data/compose/1/docker-compose.yml, /data/compose/2/docker-compose.yml ...

Hope this helps

perfect! That was what I was looking for :)

As this is one of the first search results that comes up on google when looking for the location of stack compose files, here is the location for a "standard" install on linux:

/var/lib/docker/volumes/portainer_data/_data/compose/