Waterfox has a native sidebar/vertical tab feature along with container tabs that might fill your tab group needs (I stopped using chrome before they added tab groups so I watched a 4m video on them and seems like you could get all the features and more out of the sidebar).
Waterfox has a native sidebar/vertical tab feature along with container tabs that might fill your tab group needs (I stopped using chrome before they added tab groups so I watched a 4m video on them and seems like you could get all the features and more out of the sidebar).