[Inertia] Interaction doesn't respect system scroll inertia #10830
Description
Describe the bug
Today, many UI surfaces behave poorly when scrolling on trackpads due to lingering inertia. For example, scrolling a webpage to find some text, then pressing Ctrl in preparation to copy with Ctrl+C causes pages to zoom wildly.
It's not well-documented, but we fixed that: in recent builds of Windows (later than Sept 2024's Beta KB5043166), pressing any key cancels inertia (internal link).
However, XAML surfaces do not seem to respect this, leading to runaway zoom bugs like Terminal 5708.
Why is this important?
Runaway zoom is a very frustrating behavior. It is extremely disorienting, confusing, and slow to resolve.
Apps like Terminal have implemented mitigations to prevent this behavior.
Competitors like macOS do not have this issue because most shortcuts begin with Cmd, so copying does not impact apps that implement Ctrl+scroll.
Steps to reproduce the bug
On a recent build of Windows (newer than 2024), in WinUI Gallery, on a laptop:
- Open the ScrollView page.
- Begin scrolling (with inertia)
- Press
Ctrl.
Actual behavior
Scrolling does not stop.
Expected behavior
Scrolling should stop.
Windows version
Any recent build (later than Sept 2024's Beta KB5043166) with work item 51449382 (internal link)