Caused by a bug in the recent Q824145 patch.
Microsoft probably knows about it by now.
By the time we get used to this 'new'
feature Microsoft will fix it!!
------options here------------------
Position cursor 'close' to the top/bottom of the
slider bar and it should scroll one window.
Use the mouse wheel to scroll.....as applicable
See mouse properties (Wheel tab) to adjust
Press/Hold/Slide actual slider-bar
Keyboard navigate: Leave cursor on left ausw of screen
and use other hand on keyboard. (Unless one-armed)
Up/Down Arrows (Single line!!!)
Left/Right Arrows (<---Very Slooow--->)
Pageup/Pagedown (Too obvious???)
SpaceBar = down one page (Sometimes)
Shift+SpaceBar = up one page (Sometimes)
Home/End (Top line/Bottom line -- wow)
R-click scroll area.....menu....select option
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