I wish Firefox would consider adopting some of Vivaldi's best UX improvements instead of fiddling with the size of the ultramegabar and dropping TV show promos

I wish Firefox would consider adopting some of Vivaldi's best UX improvements instead of fiddling with the size of the ultramegabar and dropping TV show promos into updates. Vertical tabs is the one that most comes to mind. For people with many tabs open, tabs at the top is a completely broken experience. Tree style tabs is OK but it doesn't remove the redundant tabs at the top, cluttering the screen. Edit: If you want to compete for market share with chrome, this is a great way to do it! =)