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.
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Module.enable require.js:1104
Module.init require.js:754
callGetModule require.js:1129
context.completeLoad require.js:1499
context.onScriptLoad require.js:1606