PageUp PageDown

[Truemotion]

I like to use command+up and command+down as PageUp and PageDown keys. But Vivaldi totally ignores my settings and instead rolls to the beginning or end of the page.... That behavior is old, as I remember it is older than 4 years. In the past, I have managed it with an external application, but now I need it to be as it should... Any other keyboard shortcut works great.