All widgets are missing

Hi there,

when we create a new post or page all Elementor widgets are is missing and we get the following JS error for this Elementor include.

Uncaught TypeError: Cannot use 'in' operator to search for 'length' in A
    at p (jquery.min.js?ver=3.6.0:2)
    at Function.each (jquery.min.js?ver=3.6.0:2)
    at n.initElementsCollection (editor.min.js?ver=3.4.3:2)
    at n.initialize (editor.min.js?ver=3.4.3:2)
    at n.h.View (backbone.min.js?ver=1.4.0:2)
    at n.constructor (backbone.marionette.min.js?ver=2.4.5.e1:24)
    at n.constructor (backbone.marionette.min.js?ver=2.4.5.e1:24)
    at n.constructor (backbone.marionette.min.js?ver=2.4.5.e1:25)
    at new n (backbone.min.js?ver=1.4.0:2)
    at n.setPage (editor.min.js?ver=3.4.3:2)

common.min.js?ver=3.4.3:2 Uncaught ReferenceError: originalEvent is not defined
    at onError (common.min.js?ver=3.4.3:2)
    at dispatch (jquery.min.js?ver=3.6.0:2)
    at v.handle (jquery.min.js?ver=3.6.0:2)

I have tried disabling all plugins & theme (ASTRA) – no change – this is not a plugin or theme conflict.
I have tried reinstalling Elementor – no change.
All themes/plugins/WordPress core is up to date.

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