Cannot save forms in v1.9.4 - POST error 400 - rest_invalid_param cf_edit_nonce

[filak]

Do You Need Immediate Help?

• YES

Is This A Feature Request?

• NO

What Version Of Caldera Forms, WordPress and PHP Are You Using?

• WordPress Version: 5.6.2 PHP Version: 7.4.11 MySQL Version: 8.0.22 Caldera Forms Version: 1.9.4

Does Your Issue Persist When You Disable All Other Plugins and Switch To The Default Theme?

• It seems irrelevant - I have tried in TwentyTwenty theme and it does not work either

What Is The Unexpected Behaviour?

I am able to create a blank form BUT I cannot save any updates/edits.

I just click on the Save button - it goes "Saving" and switch back.

I see some warnings and errors in Chrome debugger:

• warning in Console: (This seems unrelated to the issue)
  [DOM] Found 2 elements with non-unique id #caldera-forms-custom_callback

• error in Network tab:
  https://.../wp-json/cf-api/v2/forms/CF60 ... ?_locale=user - POST error 400 - rest_invalid_param cf_edit_nonce

    code: "rest_invalid_param"
    data:
    params: {cf_edit_nonce: "cf_edit_nonce není typu string."}
    cf_edit_nonce: "cf_edit_nonce is not type of [translated] string."
    status: 400
    message: "Invalid parameter: cf_edit_nonce"

What PHP Errors Have You Logged While Reproducing This Bug?

• None

What JavaScript Errors Have You Seen While Reproducing This Bug?

• None

[filak]

And I do not see the changes in the Preview either.

[filak]

Well, OK, out of any options, I have disabled the JQuery migrate plugin (set to jquery 3.3.2) which had been a life saver back then (#3650 (comment)) and I am finally able to save the form again !