In the middle of a match, a bunch of sponsorships flashed in my face covering up the whole screen, and then for the rest of my current life, ad papers flew out of my character. What happened? What did I trigger, or what weapon was used on me?
Tank grenade does that. If the ads were falling off you for the rest of your current life, that's part of a bug where the visual indicators of various effects sometimes don't go away until death. I've had the dizzy effect stuck on me personally and I've seen people perpetually stuck on fire or in a sniper's ice trap (poor assassin unable to properly cloak because you can always see this block of ice running around)