Why would the file manager need to handle smb (mounting?) I always setup smb shares through fstab and have them automatically mounted, lf shows the files just fine.
If you want a way to mount shares through your file manager, Im sure there is a way to add this to lfs config, but I don’t really understand why.
Oh in that case you may want to take a look at rclone. You can use that to configure profiles for separate shares it makes mounting and managing them very easy.