I am a new Ubuntu user.
I installed chromium and Unity WebApps Chromium extension.
Also i installed some web apps like Twitter, Facebook, Vkontakte. But they are no appeared in social hub (i don't know how to name this thing. Notification center or Friend App). Also they (web apps) don't show information like number of not readed messages in gmail etc. I opened chrome js console to see some logs.
In gmail web app I always have
In FB web app i have:
***"Port error: Could not establish connection. Receiving end does not exist. miscellaneous_bindings:236 chromeHidden.Port.dispatchOnDisconnect".***
Also web apps don't work in Firefox.