PSA: You can be punished for pre-game, post game, in game, or even a friend chat
Title is what the riot support told me, probably something known by a lot of you but it came as a surprise to me because I'm not really toxic so I was pretty shocked when I got a 2 week. Long story short, was in five man que with IRL friends, I'm black, had disc muted, was on the phone, so typed in champ select. I typed the no no word and then we loaded into game. Popped off on AP Janna(nerf dark harvest lol) enemy team got tilted stated flaming, I started saying things like "gg ez and lol" when I would blow up their zed. Just some mild stuff but still got reported. Got suspended for two weeks shortly after because the bot picked up my no no word in pregame. I thought this was kinda lame so I went to riot support. They told me what was in the title and that context does not matter and that any further punishment will result in a perma ban due to the severity of their zero tolerance policy. I'm not too worried about losing my account since I don't use chat all that much. There really is no reason to use chat at all when the "Nice try" emote exists. I totally understand my punishment whether I agree with it or not. Just thought I'd inform as many people who like myself were ignorant of this. I don't know what words flag riots zero tolerance policy but don't risk it guys even in friend chat, it's not worth losing your account.
TL;DR: Be careful what you type nowhere is safe from blitzcrank bot
Edit: Screenshot https://imgur.com/a/9anfwhH
Edit2: Screenshot https://imgur.com/OedaJ2z