Laravel 5.5 and CKEditor Options

I want to use some of the optional extras, specifically video embedding, in CKEditor.

I have downloaded the entire thing to ckeditor in the public area, and in the plugins directory there is the video.

I start with the CDN of CKeditor:

<script src="//cdn.ckeditor.com/4.7.3/full-all/ckeditor.js"></script>

and then I add the option for the video plugin:

<script>
 CKEDITOR.plugins.addExternal( 'video', '', 'video.js' );
</script>

(The video.js actually is in a subdirectory dialogs which I have tried as well).

I can CKEditor which appears on my page but no video button.

Anyone any ideas please?

via Chebli Mohamed