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
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Indeed it doesn't - github seems to be playing up for me to be able to commit the fix to it at the moment. I have fixed it locally and the change will get published as soon as the internet decides that it likes me again.The issue I see with the Yes/No plug-in is that it does not show in details view.