So I tried to find what tab groups are but most of the results are feature request threads so apologies if this isn't what you want.
Waterfox will soon be adding some sort of tab grouping feature akin to what tree-style-tab extension does. Here's the blogpost about it https://www.waterfox.net/blog/waterfox-x-treestyletab/
Again I'm not sure if that type of grouping is what you're looking for but if it is consider watching out for the feature release. Longtime waterfox user and haven't had many complaints, Alex has quickly responded to the two issues I made in the github including a feature request that got added within a week (ability to unload tabs with right click).
" shows a simple YouTube homepage without any videos or tips on what to watch."
I've had watch history off for like 7 years now and I haven't had videos on my homepage for at least 2 years now. Hasn't bothered me a bit, I only watch my subscription page and find new people with the recommendations based off of their videos.