Granted, I've been away from Drupal for awhile, so this could be PEBCAK. :) Nevertheless, I really am not sure how to do this anymore now that the system table is stored in CMI.
I applied the patch from #1741498: Add a device preview bar to Drupal core which adds a new module called Responsive Preview.
Go to Admin > Extend and... no Responsive Preview module.
Nothing in the help there explains what to do to get new modules to show up. It does say "Always run the update script each time a module is updated." so I do that, but that doesn't change the listing.
So... what am I missing? :)
