UserAgent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36

Steps to reproduce the problem:
1. Click & hold on the scoll bar control
2. Drag the control to another position
3. Count 1sec without moving it
4. Release the button
5. Move the mouse up/down, and the window will scroll with you (you can even move mouse left/right and scrolling will still be in "stick" mode.
6. Now use the keyboard up/down/pageup/pagedown keys to scroll a whole more. It works as expected. Scroll some pages down using the keys.
7. Finally move the mouse again - WAIT! the page jumps back to where it was just before I used the keys!!!

What is the expected behavior?
Up to step 5 I think the behaviour is expected, right?  But using the keyboard should disable the "sticky scroll" mode.

What went wrong?
Moving the mouse after using the keyboard makes the page jump to scrollpoint set after step 5.

Did this work before? N/A 

Chrome version: 59.0.3071.115  Channel: stable
OS Version: 6.1 (Windows 7, Windows Server 2008 R2)
Flash Version: 

Pls contact me if you need clarification. I'm willing to help.