Grumble about messaging conversation indistinguishability

Why, why! oh mighty God, do Slack, Skype, Messenger, iMessage, and every other messaging application not make any visual distinction between two or more conversations? Squint at the screen and you will see that every conversation looks identical -- even across messaging applications! How many times have you and I and, most likely, the developers of these applications sent a message to the wrong conversation? Lots. Please, oh pretty please, allow me to at least change the background color of conversations.