Microsoft just released a new feature for Microsoft Edge Dev and Canary that improves scrolling. The feature moves pointer-based scrolling of the scrollbar to the compositor thread rather than the main thread. As a result of this move, dragging the scrollbar with your mouse feels less janky, especially when a site is busy. Techdows first spotted the change.

The feature is enabled by default in the Dev and Canary versions of the new Microsoft Edge, but you can also change its setting through about:flags.

You can test the feature out yourself using this demo site. On that site, you can enable an animation and induce main thread jank. This jank crowds the main thread and normally would make scrolling feel uneven and awkward. By moving over to a different thread, the scrolling feels much better. You can see how the feature affects scrolling in the video below, which the Microsoft Edge Dev team shared on Twitter.

We've rolled out new scrolling improvements in Canary and Dev that make scrolling via scrollbar more responsive when the main thread is busy (for example, during long-running JavaScript).



Try it out and let us know what you think! More scrolling improvements coming soon. pic.twitter.com/akHxRlKOCh — Microsoft Edge Dev (@MSEdgeDev) March 19, 2020

This is another little improvement that Microsoft is making to scrolling within a Chromium-based browser. The Microsoft Edge Dev team said on Twitter that "More scrolling improvements [are] coming soon."