Missing E is a browser add-on that activates whenever you're in your Tumblr Dashboard and adds some additional functionality. You may not end up using all of them but for something as handy as "Magnifier" (so you are never yanked away from the Dashboard to view an image) makes it entirely worth it. Tumblr users catch a lot of flak for failing to attribute the source of content on their posts. Turns out, back in September of last year the Tumblr Staff did a great job of adding Content Attribution tags available to any theme to properly show where content is coming from. The only problem with these tags is that they failed to include them in the official documentation of how to make your own custom theme. So, unless you were really digging, you'd have no idea they existed. It's unfortunate because it is extremely easy to integrate into a theme and should be a standard for everyone! Building a custom Tumblr theme is actually a lot of fun and, hopefully, the Content Attribution tags are the only ones missing from the documentation!