With two dragging handles on the sides of the scrollbars you can change the size of the view with a single drag.
Example of how it works in the piano roll and project view of Reaper:
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Yessssssssss + 1000000
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+1 That example above from Reaper is very nice!
Why accept a making a significant portion of the users unhappy? Some people want/need wider scrollbars, some want/need narrower. No arguments, reasons, or justifications can undo this divergence.
The only GOOD answer is to accommodate ALL users by coding in the flexibility to allow the scrollbar width to be changed by the user.
While at it, adding the incremental arrows and allowing for sensitivity to be set also would be SUPER!
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