Dreamirl is a gaming platform I made using on client BackboneJS (+jquery & underscore), Bootstrap, RequireJS, moment, less, stash, and few other stuff.
NodeJS with Socket.io, mongodb, express, logger and much more middle-ware inside to power-up the server.
This platform run as Steam or Desura but inside the browser. I'm also planning a standalone version using nw-js.
It's using sockets to create a permanent real-time connection and avoid any lag when switching page, submitting stuff, whatever.
Technically it's interesting, I made an overlay for my games which is named "Nebula". This overlay is downloaded by the game during the loading, and then it's deploying inside the DOM to create the same API as the Dreamirl client.
Give it a try, creating an account is free, password are encrypted and I don't sell any information to anyone.
Also it's should be compatible with all major browser, starting at IE9 (maybe below, but I don't care because Canvas2D start from IE9...).