[Image2, ACF] Content of figcaption remain once the tag is stripped out in a widget

[Olek Nowodziński]

Problem: If user explicitly disallows figcaption in ACF, figures are upcasted but the contents of (just stripped out) figcaption remain as a plain, non-editable paragraph within widget's body.

Expected: Once figcaption is disallowed, its contents should be removed from the widget. Such widget should be upcasted either to an inline widget or a block widget without caption (to be decided).

[Piotrek Koszuliński]

cc

[Jakub Ś]

To reproduce:

1. Use below configuration:

   CKEDITOR.replace( 'editor1', {
       disallowedContent : 'figcaption',
       extraPlugins : 'image2'
   });
   

2. Switch to source, paste below code and switch to wysiwyg:

   <figure class="image right"><img alt="Saturn V carrying Apollo 11" src="assets/sample.jpg" />
       <figcaption>Podpis</figcaption>
   </figure>
   

NOTE: disallowing figcaption disables ability to create image with signature from image2 dialog.