Interesting find. I could use this idea in Stylebot (http://stylebot.me). It's a Chrome extension that allows you to live edit a custom stylesheet for any page on the web.
It looks like he just uses the "contenteditable" property ( http://valums.com/edit-in-place/ ) to make it editable, and then displays it as a word-wrap: pre element.
While I can't think of any immediate applications, I had never realized that contenteditable was so widely supported. I'm going to have to try using it in my next project...
I doubt that is a problem with Adblock itself. I guess you mean you are using Adblock Plus with a filter subscription? Check what things are filtered on that page based on your filters.
Oh, sorry, just realized that may have been interpreted incorrectly. The page works, but only with the example CSS - the Adblock code on the page is uneditable.
