I'm using the latest nightly and I decided to add back the Facebook Messenger which uses the Social API (since today's release was talking about two new providers being added). Once I disabled the "sidebar", I did not have the icons on the menu bar that I used to have for the Facebook Messenger. I can get the sidebar back with "View->Sidebar->Facebook Messenger" but I don't have the icons that allowed me to know if I had notifications from Facebook w/o using the sidebar. I can't even use "customize" to add them because they don't exist. Is this done purposely?

Looking into a sidebar open button in bug 960198. The change with buttons (ie. no more multi-button that facebook has used) is intentional, things will clear up before release.