Maybe chmod 000 the .desktop files works.

What does `lsblk -f say?

I only have experience with nextcloud deck. It generally works. The permissions for other users are not very intuitive. I had problems with embedding pictures.

The android app has room for a lot of improvement. Especially regarding support for markdown.

https://youtube.com/watch?v=WjABILVAz5Y

The channel is called Blind.

It looks like /dev/sdb2 is your efi partition. Your disk names probably got swapped. It might be worth to switch to UUIDs. lsblk -f gives you your filesystem types and UUIDs for your partitions.

Edit: This is incorrect.