In a detailed blog post, Microsoft has talked about the available and upcoming Chromium Edge scrolling improvements. Microsoft has made some scrolling improvements and will be investigating to add more in the future to match the Windows personality.
Available scrolling improvements:
Improving Chromium scrolling to better match Windows personality
We’ve been hard at work in the Chromium code base to bring the best aspects of Microsoft Edge scrolling to Chromium while looking for opportunities to improve upon it. These changes are now enabled by default in all channels of the new Microsoft Edge – try them out and let us know what you think!
Improved impulse and touch fling animation curves
One of the improvements we’re bringing to Chromium is a new animation curve for scrolling. This curve gives every mousewheel, keyboard or scrollbar scroll as well as touch fling the “smooth” personality seen in the previous version of Microsoft Edge.
Overall, the animation is more tactile with slightly longer with less abrupt changes in velocity. We encourage you to try it out today in the new Microsoft Edge on a Windows 10 device by scrolling using the mousewheel, keyboard or scrollbar or by using touch to do a fling.
Known issue: We’re refining the fling animation curve on some legacy non-PTP touchpads. Stay tuned for Insider announcements of further improvements in that area!
You can see some of the upstream changes in Chromium at the links below:
- Add Impulse-style scroll animations
- Refactored ScrollOffsetAnimationCurve to facilitate new animations
- Implement new Windows fling animation curve
- Fling Animation Curve – Part 1
- Fling Animation Curve – Part 2
Percent-based scrolling
Chromium browsers use a fixed scroll delta value (100px per mousewheel tick, 40px per scrollbar button click or keyboard arrow press). We are changing this behavior to match previous versions of Microsoft Edge, which use scroller height to compute scroll deltas. Percent based scrolling is a great functional addition making it much easier to navigate smaller scrollers.
You can see some of the upstream changes in Chromium at the links below:
- Add percent-based scrolling for Windows
- Add main thread percentage scrolling for keyboard and scrollbar
Overscroll bounce effects on the root scroller
Overscroll bounce is a signal to the user that they’ve reached the end of a page while scrolling – you might have heard similar effects sometimes referred to as “rubber banding”. In user studies we conducted 71% of participants expressed a preference for the overscroll bounce effect.
We’ve enabled this both for touch input and for PTP touchpad input in Microsoft Edge when scrolling in any direction. Following initial support for the page’s root scroller, we’re investigating ways to enable this effect for sub-scrollers within the page in a future update – stay tuned!
Changes to previous Microsoft Edge personality based on the feedback
Scroll chaining vs. scroll latching
While we’ve brought much of the most-liked personality back to the new Microsoft Edge, we’re also using this opportunity to re-evaluate some existing behaviors our users were less fond of.
Consider scroll chaining, the effect that scrolls the parent scroller once the sub-scroller has reached its bounds. In the past we heard a substantial amount of feedback where many users considered this to be a bug on several popular sites.
Chromium already has a concept of scroll latching, when all scrolling manipulation is directed to the same scroller until a certain amount of time passes with no scroll changes.
The main difference between chaining and latching is that the former can occur mid-gesture if the sub-scroller bounds are reached, while the latter only works when the scroll gesture is started.
We’ve validated this change with user studies and noted that virtually everybody (97% favorable feedback) preferred this behavior if the overscroll bounce was also available – further validating our plans to invest in that effect for sub-scrollers.
As a result – we are not planning to bring scroll chaining to Chromium.
Fling boosting
Another thing we’re integrating with our animation curve that was already in Chromium is fling boosting. This is the experience where multiple sequential flings will continue to increase velocity. Fling boosting is great when you’re trying to quickly progress through the document and don’t care about precise content – only getting to your destination as quickly as possible.
We’re actively working on enabling fling boosting with the new scrolling personality and look forward to your feedback in the near future as we release this feature.
Quick Flick
Finally, we’ve decided to remove quick flick feature. This feature produced large scroll deltas when a user made a short but fast flick gesture on the screen.
In our user studies, we couldn’t find users who could reproduce it consistently. In addition to that, most feedback received for this feature was due to accidently performing a quick flick and the user not expecting the page to scroll so far.
Microsoft has also shared some of Edge scrolling personality improvements they are investigating and currently working on.
Our scrolling personality backlog based on your feedback
We’re looking to make the new Microsoft Edge not just a carbon-copy of EdgeHTML, but an improvement that combines the best of Chromium with the best of EdgeHTML. To that end we’re evaluating other personality improvements and are investigating how to enable those in the coming updates, including:
- Overscroll effect in sub-scrollers
- Pinch zoom overscroll effect
- More tuning for individual personality effects and interactions based on your feedback
Please note – as we uncover engineering realities our plans might change!
