I propose removing the cancel button in quick edit mode. This button is positioned first from the left, similar to the post button in normal mode. I've experienced instances where I accidentally cancelled my long edits on SMF, and it seems to happen here as well. Although it appears that the save option is on the left here. Nonetheless, it would be better to remove the cancel button. The normal edit mode seems fine without it somehow.
I don't think drafts are part of the quick edit, that may be an option to at have any work saved in the event of a wrong click. Just a thought.
We could add the "are you sure" confirmation dialog. Possibly make it smart enough to only present that if there were edits.