You asked, we built it: Firefox tab groups are here  | The Mozilla Blog
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What happens when 4,500 people ask for the same feature? At Firefox, we build it. Tab groups have long been the most requested idea on Mozilla Connect –
  • bambooEnglish
    3·
    4 days ago

    They do work in vertical tabs, but only one level. You can’t have nested tabs as far as I can tell.