Reinventing the wheel
I don't like the amount of wheel reinvention in this extension. I saved  but I never got to see action=edit or veaction=edit: the page was saved via the API, from within Special:ContentTranslation.
The result of this operation is that all the editing environment will need to be recreated from scratch, piece by piece, for an unknown benefit (for instance phab:T76178). I suggest to get rid of all this and send the user to action=submit, as VisualEditor does for commuted edits, every time some text or work needs to be saved on the wiki (i.e. made visible to other users; I hope nothing is being saved other than in the revision table, but I'm not sure). --Nemo 14:26, 3 December 2014 (UTC)