Add an option to opt-out of the redesign

I know you guys have probably been receiving a bunch of these requests but it's an objectively good idea. Change it back. None of the changes you've made are good in any way and they don't actually help the idea that you're making this platform "friendly." The way all the pings and channel mentions look makes it feel more clinical than it was before you even altered it. You're probably too prideful to revert the change entirely but at least give us the option, some switch in the menu to go to the old design.