Firefox 29 and later do not have a built-in option to move the tab bar below the main navigation toolbar. There are add-ons for this, including Classic Theme Restorer. I don't have any personal recommendations.

Thanks for the response but Classic Theme Restorer is no longer available and I could not find a replacement. Looking back at portage I suspect it was version 38.8.0 that used to display tabs "properly" but an increasing number of websites won't display properly with it, hence the upgrade. I guess I'll find a workaround or replacement.

I'm sorry, but why do you say this:

Classic Theme Restorer is no longer available and I could not find a replacement.

Is there a difference between Windows and Linux for this extension? It definitely is still available on Windows:

https://addons.mozilla.org/firefox/addon/classicthemerestorer/

Hi, if you don't mind squared tabs (the reason I use it) try this - https://addons.mozilla.org/en-US/firefox/addon/squared-australis-tabs/ (There is an option to have tabs on bottom).

Wow. I just searched for Classic Theme Restorer again and again came up dry.. however, this time I noticed a "more" button on the bottom. Clicking there pulled up a page with CTR and only CTR on it. Odd behavior but anyway, thanks for making me look again.

Thanks also to Scribe, I don't care much about the tab shape although I suppose rounded corners would be more traditional.