Board Thread:Support Requests - Getting Started/@comment-25236122-20140822160749/@comment-1038387-20140822230725

Disregard that last post. Short google search...

That green jigsaw is a part of Wikia's Vidual editor. It allows quick access to the editor - it's essentially an "edit" button. If you want to get rid of it, you're going to have to switch to Source Mode.