How to disable moving a window by its edge adjacent to scroll bar? In Mac OS X Yosemite, I find that the scroll bar is a small target for the mouse, and sometimes when I wish to scroll, I end up moving the whole window by grabbing its edge to the right of the scroll bar.  This is never the behavior I desire.

How can I disable the ability to move a window by grabbing anything other than its title bar?
I try scrolling with scroll bar because there is a scroll bar. Sometimes it's better than scrolling with mouse. (smooth scrolling)

To change, go to System Preferences: General settings -> Show scroll bars -> Always