Here on Firefox 4.01. And the option you look for is still there but they replaced it's position: it now is on the right of the URL bar together with the refresh-button and the add-bookmark-button. Personally I think it's a bad place for that back-button because it was perfectly and logically placed where it was.

Nope! Sorry. That's not it. That was always there and simply brings up recent browsing history. I'm talking about the little arrow that brought up the previous pages relevant to the open tab. So you go into a site and then click on a link and then another link and then a thirsd link, and this arrow drops a menu which lets you go back to the original page. In 4 you have to go back page by page.

ACTUALLY I have just found it totally by mucking about. It's a right-click on the back arrow!!! Too subtle for me, that one.

The drop-down marker was removed from the Back/Forward button in Firefox 4.

You can do one of the following:

• right-click the Back/Forward button to show the drop-down list
• while on the Back/Forward button, HOLD down the left-click mouse button until the drop-down list appears
• install this add-on to add the drop-down marker to the Back/Forward button: https://addons.mozilla.org/en-US/firefox/addon/backforward-dropmarker/