I implemented differential sync (https://neil.fraser.name/writing/sync/ https://neil.fraser.name/writing/sync/) mostly because I couldn’t understand anything el

I implemented differential sync (https://neil.fraser.name/writing/sync/ https://neil.fraser.name/writing/sync/) mostly because I couldn’t understand anything else and seemed simplest in my grugnotes.com app -- and while the app is pretty janky and not fully real-time, it does get your example merge right regardless of who comes back online first. In the case the deletion comes online first, the 'colour' version is thrown out and not saved in edit history. I’m sure there’s a lot more wrong with it, have no idea what would happen with more than two users, but for my case I’m happy with it. :)