Hi, I used to use horizontal tabs and today I updated firefox, found out that there is vertical tabs feature, and I set it out!
When I was browsing with horizontal tabs, I use `cmd` + `left/right` to navigate between tabs. Intuitively thinking, I thought I could navigate with `cmd` + `up/down` on vertical tabs but it didn't work out.
As visual representation changes, I think it should handle its navigation command vertically also.