The editors features include
I have found this add-on really useful in the sites I make as I find a lot of what I enter into a page is HTML and the current methods either stripped out markup or were hard to use.
This add-on has been tested on the latest versions of Chrome, Firefox and IE.
It relies on Jquery being loaded which C5 should take care of. Other dependancies are loaded by the add-on.
I am not a PHP developer or full time programmer so I can't guarantee instant support but I will endevour to support this and answer any questions as best I can.