For running J!5.1 you must https://fabrikar.com/forums/index.php?wiki/update-from-github/ or include the new file manually https://fabrikar.com/forums/index.php?threads/joomla-5-1-and-fabrik-cannot-find-files-error.54473/post-285151 See also Announcements
Please see our announcement here.
WHERE {thistable}.id IN (SELECT user_id FROM j25_user_usergroup_map WHERE group_id = 10)
I mean one new list with a new database table, without content type (resp. content type = default), adding manually one dbjoin to a simple table , without any Data-where etc.This list is new