[WASM] `ScrollBar` isn't going to appear while dynamic content is being aggregated

[sigmarsson]

Scrollbar isn't showing up in the scroll viewer

        <nowinui:ScrollViewer Grid.Row="1"
                              VerticalScrollMode="Auto"
                              VerticalScrollBarVisibility="Auto">
            <wasmcc:WebAssemblyHtmlControl HtmlContent="{x:Bind HtmlContent, Mode=OneWay}" />
        </nowinui:ScrollViewer>

HtmlContent is aggregating <div> elements in the view model.

Expected behavior

Vertical scroll bar appears as property HtmlContent is aggregating.

How to reproduce it (as minimally and precisely as possible)

Workaround

Environment

Nuget Package:

• [ ] Uno.UI / Uno.UI.WebAssembly / Uno.UI.Skia
• [x] Uno.WinUI / Uno.WinUI.WebAssembly / Uno.WinUI.Skia
• [ ] Uno.SourceGenerationTasks
• [ ] Uno.UI.RemoteControl / Uno.WinUI.RemoteControl
• [ ] Other:

Nuget Package Version(s):

Affected platform(s):

• [ ] iOS
• [ ] Android
• [x] WebAssembly
• [ ] WebAssembly renderers for Xamarin.Forms
• [ ] macOS
• [ ] Skia
  • [ ] WPF
  • [ ] GTK (Linux)
  • [ ] Tizen
• [ ] Windows
• [ ] Build tasks
• [ ] Solution Templates

IDE:

• [ ] Visual Studio 2017 (version: )
• [ ] Visual Studio 2019 (version: )
• [ ] Visual Studio for Mac (version: )
• [ ] Rider Windows (version: )
• [ ] Rider macOS (version: )
• [ ] Visual Studio Code (version: )

Relevant plugins:

• [ ] Resharper (version: )

Anything else we need to know?

[jeromelaban]

Thank you for the report. Can you provide a full repro sample attached to the issue ?

[sigmarsson]

@jeromelaban yes, please consider the respective commit here.

[dr1rrb]

Direct link to the commit : https://github.com/sigmarsson/6051/commit/29ba9d2c8459e854978bdbd46123d2786832e3f7