Every used CKEditor’s WYSIWYG, inserted some code in Source view, then when you reverted to WYSIWYG the code disappeared?
The default setting of CKEditor strips the html, and extra bits of code that aren’t entered normally bu users. This is normal of course. It’s just cleaning up code the way it’s supposed to.
But there may be times when you need to enter code, like embed code or add some classes. Here’s how to do it:
config.allowedContent = true;