Bug 234433 – [WPE] Kinetic scrolling doesn't work in overflow scrolling

• Status: RESOLVED
• Resolution: FIXED
• Component: WebKitGTK

WebKitGTK only does kinetic scrolling when scrolling the whole document, but not when scrolling other elements with `overflow: scroll`.

Another difference I noticed between page scrolling and overflow scrolling: when using arrow keys and PgUp/PgDn to scroll, page scrolling is animated (like `scroll-behavior: smooth`), but with overflow scrolling, it scrolls instantly without any animation.

[Pablo Saavedra]

https://people.igalia.com/psaavedra/scroll_horizontal.html
https://people.igalia.com/psaavedra/scroll.html

[Pablo Saavedra]

I can confirm this defect is also happens in WebKit WPE.Tested in:

* https://people.igalia.com/psaavedra/scroll_horizontal.html
* https://people.igalia.com/psaavedra/scroll.html

[Alice Mikhaylenko]

I can see kinetic scrolling with your samples with WebKitGTK at least.

[Pablo Saavedra]

(In reply to Alexander Mikhaylenko from comment #4)
> I can see kinetic scrolling with your samples with WebKitGTK at least.
  
Not the case of WPE. Not at least using a build from trunk.

Tested on Arch Linux, with webkit2gtk-4.1 and webkit2gtk-5.0 2.36.0.

Kinetic scrolling seems to be working with GTK 4. But overflow scrolling with PgUp/PgDn still has no animation.

On GTK 3, overflow scrolling is neither kinetic nor animated.

[Alice Mikhaylenko]

Huh. Didn't think it would depend on GTK3/4.

I see they are using different codepaths when creating a NativeWebWheelEvent though, I guess it has to do with that then.

[Pablo Saavedra]

Update: Works on Ubuntu for WebkitGTK (libwebkit2gtk-4.0-37:amd64                       2.36.6-0ubuntu0.22.04.1)

[Pablo Saavedra]

Update:

*  Works on Ubuntu for WebkitGTK (libwebkit2gtk-4.0-37:amd64                       2.36.6-0ubuntu0.22.04.1)
* But not kinetic at all in overflow elements for (libwpewebkit-1.0-3:amd64 2.36.0-2ubuntu3)

[Pablo Saavedra]

Pull request: https://github.com/WebKit/WebKit/pull/3770

[EWS]

Committed 254099@main (431d9f7c6bc7): <https://commits.webkit.org/254099@main>

Reviewed commits have been landed. Closing PR #3770 and removing active labels.