Unable to add content to third tab and so on.

Problem/Motivation

When using the tab layout, I can successfully add paragraphs as content to Tab 1 and Tab 2. However, when attempting to add a third tab and so on, I get this error and can no longer add other layout sections or paragraphs: Failed to execute 'appendChild' on 'Node': The new child element contains the parent.

Steps to reproduce

Avk

1. Add a layout section of type tabs
2. Add paragarphs/content to tabs 1 and 2.
3. Add a third tab
4. Attempt to add paragraphs within tab 3. Get the error and fail to add anything.