spare lion
Via the app on Steam you have the option to Report a player, and being abusive is one of the options. From memory (not played for a while, obviously) you could click on the player at the top of the screen and the Report option was there. Might be different if on mobile, not sure.
Of course, what happens once you have reported a player, I do not know. I'd like to think that the report was at least viewed, and maybe some form of action is taken, but there doesn't appear to be a system in place where you hear back etc, so those reports could just be sent and ignored.
The other thing I would suggest, is to not engage, trolls will be trolls, so if you feed 'em, they'll just keep coming back. If the conversation starts going badly, stop responding. Especially if you plan to report them and a copy of the chat history is visible, I doubt it will do you any favours if you have also been argumentative, rude, insulting etc etc.
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