Allow to drag and drop nested paragraphs

A but more precise with this:
I am defining 3 paragraphs. 1 for a single layout, 1 for the accordion, 1 for the accordion item.
Then I have in the entity a paragraphs revision for the paragraphs which is using layout builder.
Then I have the 1 column layout use the stable paragraphs.
And that is how it is indeed the problem is reproduced. The patch fixes the issue. +1 RTBC. Tested in vanilla Drupal

Thanks for the MR - it sounds like this will work for users running into this specific issue, and passes tests.

I think we should probably think through this issue a little more though and consider changing LP form classes to use the EntityForm interface. Obviously this would change the API, so needs a little more consideration. Perhaps we can implement EntityFormInterface ComponentFormInterface for backwards compatibility.

Marking as needs work so we can continue to work on the issue.

The provided MR only resolves the Ajax error, but the nested paragraph issue still persists. I'm using version 2.1.0. Now, each paragraph is being treated as a new 'ajax-new-content'. I've attached a screenshot: , which shows the issue when using 'Layout Paragraph' as a widget. Additionally, I’ve attached a video: Paragraph Drag Drop issue → , demonstrating the problem when using only the 'Paragraphs (stable)' widget.

Instead of loading in a single container, each paragraph is split into its own container, and we are unable to drag and drop the paragraphs.