Sure. The editor doesn't store HTML for editing - it uses the browser's DOM representation of the HTML. So when you ask for your HTML back from the editor, it queries the DOM and rebuilds your HTML. The returned HTML might not be exactly the same as what you started with...
In particular, tag attributes may appear in a different order. The order isn't defined, but is usually consistent within a single browser.
Other things that might change include removal of invalid attributes or tags and added closure tags.
Re: html content problem
In particular, tag attributes may appear in a different order. The order isn't defined, but is usually consistent within a single browser.
Other things that might change include removal of invalid attributes or tags and added closure tags.