[.NET 10 Preview 7] Poor CV performance, ghosting, crashing on Windows

[daltzctr]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

When using a CollectionView on Windows with a complex datatemplate (the issue is more exaggerated the more complex data template), you will observe ghosting while scrolling and low performance. Scrolling will "stutter" and mutating the datatemplate (setting a visibility property from true to false) in bulk can sometimes cause a COMException and a crash (no stack trace, COMException is empty even with Just My Code disabled and mixed debugging on).

The below video is captured running in release mode.

PoorCVRepro_kU7gkx43ey.mp4

Expected Behavior

High performance scrolling with no "jittering", no crashing when children dynamically updated, just generally more stable.

Steps To Reproduce

1. Create a collectionview binded to ~2000 items
2. Create a complex datatemplate. The more complex the datatemplate, the better.
3. Scroll to observe poor performance, jittering, ghosting.
4. Mutate the children in bulk (for example, bind to a Visible property and set half of them to False
5. Observe crash (sometimes)

Link to public reproduction project repository

https://github.com/daltzctr/PoorCVRepro

Environment

- .NET MAUI CommunityToolkit: None
- OS: Windows 11 26100.4946
- .NET MAUI: .NET 10 Preview 7

Anything else?

No response

[jfversluis]

You specifically mention .NET 10 preview 7, does that mean it worked better in earlier versions? If yes, which?

[daltzctr]

This is not a regression and pretty much has existed since at least .NET 8.

I noticed the past issues were low quality without repros, so I figured with the focus on performance, that hopefully this can be a focus for .NET 11.

For reference, a similar layout in native WinUI ListView does not reproduce the ghosting, so this is particularly aggregious for MAUI.