Nextcloud AIO - Best way to start with Fulltextsearch + Group Folders (now Team Folders) and let it index while Nextcloud is up?

Hey everyone!

I posted the same problem as discussion in nextcloud / all-in-one: https://github.com/nextcloud/all-in-one/discussions/7269
I was told to also post it here. So here it is.

I´m about to migrate a nextcloud instance, which is installed on a shared web hosting system without CLI access and a lot of problems.
I got Nextcloud AIO running as a test instance on a new VPS i got for that and migrated our old instance.
With the VPS we want to activate the Fulltextsearch.
I already tested it and it worked quite well for texts outside of group folders (now team folders).
After activating indexing group folders in the Fulltextsearch settings, it didn´t change anything.
So i reseted the index this way: https://github.com/nextcloud/all-in-one/discussions/2509
It ran so long, that my borg backup broke the indexing process and it was not able to perform a backup.
I had to stop the backup process on CLI and start the containers again.
Than i could see, that the indexing worked for some group folders files, but not all.
So i deactivated borg backup and started all containers again and now the nextcloud is down since 2 days and the indexing is still running.

Hope these information are useful for my questions.

Activating the Fulltextsearch container, waiting for the indexing of all non group folder files, activating the Fulltextsearch for group folders, resetting the index and waiting for a full index is very time consuming. I´m 4 days in and most of the time the nextcloud is offline because of the indexing.

Is there a way to activate indexing group folders for the first indexing?

Is there any way to let the indexing run in the background while the nextcloud is already up?

Is there a way to create a index of the same files on a copied machine and put it in a live environment?

I just try to find a way to migrate our production environment without having it down for more than a week.

Thanks a lot!
Let me know if you need any information or if i shall test anything.
At the moment it is still a test environment and i can do everything. ;)

Read discussion #7269 and the reset procedure in discussion #2509 first, then trace how FulltextSearch handles group folders and indexing while the containers are running. Done means establishing a supported answer or implementation for the three migration and background-indexing questions without requiring a prolonged outage.