Scrollbar trails increasingly behind mouse pointer position while scrolling Library Manager

[per1234]

Describe the problem

The Arduino IDE Library Manager view displays a list of libraries matching the user's search query. Due to the large total number of libraries, the list will often be much longer than can fit in the vertical dimensions of the view, in which case the user may scroll through the list of results using the scrollbar on the right side of the view.

🐛 The scrollbar trails increasingly behind mouse pointer position while scrolling.

To reproduce

1. Open the "Library Manager" view.
2. Type servo in the "Filter your search..." field.
   ⓘ This is only an arbitrary example of a common search query that might return enough results to require scrolling.
3. Click and drag the scrollbar downwards.

🐛 The position of the scrollbar trails increasingly behind the mouse pointer position. If the Arduino IDE window is near the bottom of the screen, it may even become necessary to stop and "grab" the bar once more in order to move it all the way to the bottom position.

Expected behavior

Scrollbar position always matches mouse pointer position.

Arduino IDE version

2.0.0-rc9.2.snapshot-0d545be

Operating system

Windows, Linux

Operating system version

Windows 10, Ubuntu 20.04

Additional context

The issue was introduced in #1361

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Related: #1380