Developer Preview Option Removed
The Developer Preview option that used to exist under Version is now gone. Because of bugs in recent releases, I turned off Dev Preview and can't get it back on. I have never noticed any difference with Dev Preview on so maybe there is no value, but I am one of the leaders at my company pushing for adoption of Teams, so I'd like to be closer to the "inner circles" rather than farther away, if possible.
Rob Syner commented
it's available from 'about' as we have switched it on to test adaptive cards with our bot. However I can't enable it on mobile which is annoying.
It's available on the mac version. don't understand why it is now gone from the windows version