It's usually been salespeople trying to sell me stuff when I've been asked to use proprietary video plug-ins. The calls with clients usually are scheduled by my

It's usually been salespeople trying to sell me stuff when I've been asked to use proprietary video plug-ins. The calls with clients usually are scheduled by my side and use our choice (now usually Hangouts or Uberconference, both of which work in Firefox without additional executables). I always just join the call-in number on the calendar invite. If needed, I just say something along the lines of, "couldn't get the plug-in installed, sorry". Not usually been a problem other than missing the screen-share presentation.