Fix JavaScript error when submitting a form that has a text_format selector set to a text format without associated text editor

Under certain circumstances, errors are triggered from editor.js which cause the panels UI to break and dump JSON commands to the screen.

Here is the fix I have so far. It would perhaps be good to understand how things get into the broken state, it looks primarily related to missing JavaScript settings as a result of no 'editor' being selected for a particular input format, but it's still possible with out of the box settings to trigger it.

The fix could be the right solution, as the same check is further down the file:

detach: function (context, settings) {
      var $context = $(context);
      $context.find('.filter-list:input').each(function () {
        var $this = $(this);
        var activeEditor = $this.val();
        var field = $this.closest('.text-format-wrapper').find('textarea').get(-1);
        if (field && Drupal.settings.editor.formats[activeEditor]) {
          Drupal.editorDetach(field, Drupal.settings.editor.formats[activeEditor]);
        }

Didn't think to check the core queue for the same module, thanks for looking at this.