Upgraded CKEditor messes with my div tags

[IntegralHack]

I used CKEditor on a project and it seemed to go well, then I upgraded it and it started manipulating my DIV tags. For example, if I have a field where I had something like this:

<div class="video-container"><iframe allowfullscreen="true" frameborder="0" height="360" src="//www.youtube.com/embed/ffffffffffff" width="480"></iframe></div>

<p>New paragraph appears here.</p>

This was fine with the prior version (I have both ACF and HTML Purifier turned off).

But now something like this happens:

<div class="video-container"><iframe allowfullscreen="true" frameborder="0" height="360" src="//www.youtube.com/embed/ffffffffffff" width="480"></iframe>

<p> </p>

<p>New paragraph appears here.</p>
</div>

My ending DIV tag gets moved to the end and an extra P tag gets inserted. Any ideas?

Thanks,

Matt

[pwired]

Similar things happen with Tinymce if the configuration of it is incomplete or missing something.

So first I would check the config of CKEditor.

[IntegralHack]

I can't find any issues in the configuration unfortunately.

[choppingblock]

I have exactly the same issue. Very annoying... seems to be a bug in CKE.

If anyone has any idea on what to configure or how to fix this (or at least where to start looking for the bug), that would really be great.