HOW do I get rid of this infernal side bar???

I jumped into my partner's site today to make some tweaks/edits and she mentioned this bar and that she had no idea where it came from. I have poured through every single link I can find and, for the life of me, I can't find a single setting that tells me what it is or, more importantly, how to get RID OF IT. 

In the pic it's on the left. 

Help. Someone. Pleeeeeeeease. 

Please post the URL for a page on your site where we can see your issue.

A link to the backend of the your site won’t work for us, i.e. a url that contains /config/.

Please set up a site-wide password, if your site is not public and you've not already done so.

Post the password here.

Adding a site-wide password does not allow anyone to alter your site. It only allows those with the password to see your site.

Please read the site-wide password and how to share a link documentation to understand how they work.

We can then take a look at your issue.

You may find How to post a forum question post useful.