This is in current FF (22.0) on W7. I think it mainly happens when trying to get back to "Current Discussions" from a particular thread. I click the back button, and a destination URL comes up in the little window at the bottom, but the tab on top says "connecting", with the little green spinning circle, but nothing ever happens. I have to click on "Chowhound" on the toolbar to return to where I was.
Again, never on other sites; just the CH site.