As a logged in user with beta access to VisualEditor using MobileFrontend, edit a new page on beta labs, e.g. http://en.m.wikipedia.beta.wmflabs.org/wiki/Apsidufapodifuasdf or some such.
Click the pencil icon to edit the page. I think this should bring up VE, but brings up wikitext editor instead.
From the gear menu, click Edit to invoke VE
Again from the gear menu, click Edit source.
VE fails to disappear. Wikitext editor does not appear. No VE controls like Bold/Italic/Link etc. function at this point.