https://www.archlinux.org/packages/community/x86_64/vivaldi/
Vivaldi Browser (stable) is now available as a package from Archlinux community Repository, so no need to build it from AUR anymore.
And yes vivaldi have some nice newer features:
Been using for a while, the sidebar feature is really nice (firefox screwed it up). I use twitter in a non-standard way, as effectively a live RSS feed:
That is tweetdeck loaded in the sidebar, works well for me 