Hi,
First of all, this already have been suggested few times before (including me with my old account). Original thread can be viewed here:
https://www.cubecraft.net/threads/allow-us-to-edit-conversations.205364/
And about suggestion, well, I'm totally agree with this idea, sometimes for example I make a mistake in grammar or anything else and I cannot fix my mistake. But I don't think this should be added just to the conversations, I think it should be implemented for profile messages post too.
Thank you for your suggestion, I'm agree!!