I noticed you have the embed and autoembed plugins shipped with CKEditor. The problem I've come across is that Oxwall strips the code. When initially pasted, this is the source of a YouTube video:
<div data-oembed-url="https://www.youtube.com/watch?v=eSjSozKL_EA">
<div style="height:0; left:0; padding-bottom:56.2493%; position:relative; width:100%"><iframe allowfullscreen="" scrolling="no" src="https://www.youtube.com/...0&showinfo=0" style="border: 0; top: 0; left: 0; width: 100%; height: 100%; position: absolute;" tabindex="-1"></iframe></div>
</div>
But after saving the post, there's no embed as Oxwall strips the code entirely (just disappears from Source code).
Is there a way to get Oxwall to allow these iframes/divs? I do have the custom HTML setting unchecked as it should be: