Hi Ilana,
Now we can reproduce it on our own JSTOR tutorial. Bummer!
JSTOR is trying to access the top-level window, which won't work when it's inside GotS: "Uncaught SecurityError: Failed to read the 'localStorage' property from 'Window': Access is denied for this document."
I see 2 options: (1) wait until we release pop-up support (we will at some point, I promise! Or you can try the master branch on GitHub at your own risk...) or (2) ask JSTOR to fix it. I'm going to look into #2 now. #1 brings some special issues and I'd rather not use it unless we have to.
Mike