Make the textarea larger + font larger, to fit nearly fullscreen on tablets.
Fix fullscreen not working with grappelli. Won't hurt anyway without it.
Make the "saving…" div more visible.
Remove an eventual box-shadow (grappelli puts one…), and add some padding to make the content breathe a little.
PEP8 happyness, protocol-independant CSS link, add commented font-awesome (didn't work, but still worth having).
Fix the button classname so now it's visible again. Probably an old jQuery syntax?
Make {Meta,Control}+e switch fullscreen. Doesn't work anyway if the cursor is already in another input field, but still faster to click in the big textarea + control+e than clicking the small button.
PEP8 love and string changes. Wait?! PEP8 in JS?? I must be sick.
Make the form.serialize() work with Grappelli too, else the POST is failing. Display an alert if no form could be found; this is much easier to understand than a failing CSRF verification when CSRF related things are all OK.