I've got an Open Atrium 2 (7.x-2.25) site, using the default Open Atrium Radix (7.x-3.5) theme. It uses the Mobile Friendly Navigation Toolar (7.x-1.0-alpha10+8-dev), but with a customised 'Open Atrium Toolbar' taking over from that.
There's meant to be a mobile-friendly version of the toolbar that appears at a certain screen-width, but on my site, at that breakpoint, the toolbar just empties itself. The new mobile icons do not appear at all.
I've had a lengthy discussion with mpotter (who seems to be the lead maintainer from Phase2), here: https://www.drupal.org/node/2381691
We've figured out that the correct CSS classes are being applied to the toolbar elements, which means that the theme's script.js is probably not being executed. The script.js file has the same user:user-group ownership as my other directories and files, and the same permissions as on a fresh, working Pantheon OA2 site.
mpotter has probably gone as far as he can go with troubleshooting, being unable to reproduce this issue... But could anybody here think of anything I might have missed?