It happened only once and I have no idea how to replicate it, but after some time (2-3 hours) of running after using "find mesh" feature it started adding not only few new battletags but several copies of each of my friends, in mimutes my friendlist looked like: Dude 1, Dude 2, Dude 3, up to Dude 8. then it stopped because of exceding 80something battletags and started deleting them and imediately adding them back in endless cycle. After /reload it stopped but battletags remained. When I tried to remove them context menu opened, I was able to click remove but nothing happened. I opened my Battlenet beta launcher and didn't found any of them there. After logging out they were all gone and everything was ok.

that's an old battle.net glitch and has nothing to do with oQueue.

it normally clears itself up (most likely after they reset the servers)