Sub-tabs in Firefox

October 2016

It is possible to have sub-tabs under firefox, to improve you browsing experience.
  • To activate this option just type chrome://browser/content/browser.xul in the address bar.
  • It is use handy if you have a small screen.
  • Note that this feature is still under developpement and that there are some bugs.
  • Note that you are not limited to only 2 rows of tabs, you can still expand it furthermore by typing the same code in the address bar of an opened tab, though it's use is quite questionable.

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