Hi @jrstaatsiii
This issue is caused by the tinyMCE editor requiring more space than you are giving it.
I can’t imagine that this was not an issue prior to the 4.3.0 update. If so, are you able to downgrade and show a screenshot?
I’m not sure what the solution is here. You need a certain amount of width of the WYSIWYG field to display all it’s toolbar buttons, and your nested situation is causing the limited amount of space.
Not sure I can provide a solution for this one.
Sorry
Thanks
E