I’ve attached the settings that work very well for me. This was after a lot of forums and reading. Has worked well now for months. My drive is formatted as ext4, maybe that is the difference here. Or that root user is not checked. But alas, I share incase it helps.
vfs objects = catia fruit streams_xattr
fruit:aapl = yes
fruit:nfs_aces = no
fruit:model = TimeCapsule
fruit:wipe_intentionally_left_blank_rfork = yes
fruit:delete_empty_adfiles = yes
Settings per share:
Global settings:
It above does work for you, you can also change the finder sidebar icon to something else, mine presents as a timecapsule. By changing the value of fruit:model = TimeCapsule.
The available finder icon entries can be found at this link: mac - Ubuntu 18.10, Samba 4.8.4 smb.conf - what are the valid values for fruit:model? - Ask Ubuntu
You should reboot your router after change, or at least restart the avahi-daemon service aswell as restart finder, in order for sidebar to reflect change.