How do I remove a synced tab in firefox?

When you click "extras", you will see settings menu.

I'm not finding an "extras" either. Where is it supposed to be?

Then you disabled it (there is a setting to only make it show up when you press "Alt" button, I have it enabled all the time)

Press left Alt button and it should appear (should look like "File - Edit - View - History - Bookmarks - Extras - Help").

I have "File Edit View History Bookmarks Tools Help" no "Extras" and pressing "Alt" does nothing. Any other suggestions?

Tools it is, sorry, my browser is in german. :P

Under "Tools" I have: Downloads Add-ons Sync Now Web Developer (with a whole bunch of sub-options, not what I'm looking for) Page Info Options Adblock Plus None of these reveal a "settings" "extras" or "Clear Private Data" option. Any other suggestions, please?

Synced tabs should expire automatically after 7 days. If you do not want to wait that long then you can consider to change the password of the Sync account temporarily to reset all stored data.