Cannot save forms

Hi,

I can no longer save/edit a flot form.

I’ve tried deactivating all other plugins but still get the same error.

I get the following error in the console.

gallery-metabox.js?ver=1.2.2.1:255 Uncaught TypeError: Cannot read properties of undefined (reading 'contains')
    at gallery-metabox.js?ver=1.2.2.1:255:29
    at dispatch (load-scripts.php?c=0&load%5Bchunk_0%5D=jquery-core,jquery-migrate,jquery-ui-core,jquery-ui-mouse,jquery-ui-slider,utils,jquery-ui-sortable,moxiejs,plupload&ver=6.0:2:43064)
    at v.handle (load-scripts.php?c=0&load%5Bchunk_0%5D=jquery-core,jquery-migrate,jquery-ui-core,jquery-ui-mouse,jquery-ui-slider,utils,jquery-ui-sortable,moxiejs,plupload&ver=6.0:2:41048)
    at Object.trigger (load-scripts.php?c=0&load%5Bchunk_0%5D=jquery-core,jquery-migrate,jquery-ui-core,jquery-ui-mouse,jquery-ui-slider,utils,jquery-ui-sortable,moxiejs,plupload&ver=6.0:2:71515)
    at HTMLInputElement.<anonymous> (load-scripts.php?c=0&load%5Bchunk_0%5D=jquery-core,jquery-migrate,jquery-ui-core,jquery-ui-mouse,jquery-ui-slider,utils,jquery-ui-sortable,moxiejs,plupload&ver=6.0:2:72110)
    at Function.each (load-scripts.php?c=0&load%5Bchunk_0%5D=jquery-core,jquery-migrate,jquery-ui-core,jquery-ui-mouse,jquery-ui-slider,utils,jquery-ui-sortable,moxiejs,plupload&ver=6.0:2:3003)
    at s.fn.init.each (load-scripts.php?c=0&load%5Bchunk_0%5D=jquery-core,jquery-migrate,jquery-ui-core,jquery-ui-mouse,jquery-ui-slider,utils,jquery-ui-sortable,moxiejs,plupload&ver=6.0:2:1481)
    at s.fn.init.trigger (load-scripts.php?c=0&load%5Bchunk_0%5D=jquery-core,jquery-migrate,jquery-ui-core,jquery-ui-mouse,jquery-ui-slider,utils,jquery-ui-sortable,moxiejs,plupload&ver=6.0:2:72086)
    at s.fn.<computed> [as click] (load-scripts.php?c=0&load%5Bchunk_0%5D=jquery-core,jquery-migrate,jquery-ui-core,jquery-ui-mouse,jquery-ui-slider,utils,jquery-ui-sortable,moxiejs,plupload&ver=6.0:5:8557)
    at adminApp.min.js?ver=1.0.40:33:310513

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