Support Prefers-reduced-motion if Animations Disabled
If a user has turned off Animations in Vivaldi, report this CSS media query to pages as true to allow them to reduce the animation in Web pages as well.
Good for both maintaining themes and for accessibility.
Could be nice to also turn this on as a page action or a site specific setting.
Firefox 63 now does this by default: https://mobile.twitter.com/andreasbovens/status/1054825066519846912