I used X-Ray Goggles by Mozilla to edit twitch.tv, one of my favorite websites where video game streamers have channels where you can view their gameplay! Below is the link to the website I edited
Check it out!
The editing was pretty simple, except one time when I was editing it, I accidentally clicked on a link that caused the page to change and I lost all my work, so that was fun! It was okay though because I just retyped everything easy peasy.