Some bindings do not update anymore with 10.0.50 + MauiXamlInflator=SourceGen

[markusroessler]

Description

Some compiled Bindings do not update anymore with MAUI 10.0.50 and <MauiXamlInflator>SourceGen</MauiXamlInflator>. See sample app.
Seems to only affect property bindings on the Page itself.

Steps to Reproduce

• Start the sample app: https://github.com/markusroessler/MauiCompiledBindingBug
  -> The MainPage IsVisible property should toggle every second - but nothing happens
• Downgrade to 10.0.41 or remove <MauiXamlInflator>SourceGen</MauiXamlInflator>
  -> Bindings works again

Link to public reproduction project repository

https://github.com/markusroessler/MauiCompiledBindingBug

Version with bug

10.0.50

Is this a regression from previous behavior?

Yes, this used to work in .NET MAUI

Last version that worked well

10.0.40

Affected platforms

Android

Affected platform versions

Android 16

Did you find any workaround?

No response

Relevant log output

[MihuBot]

I'm a bot. Here is a possible related and/or duplicate issue (I may be wrong):

• [Regression] 10.0.50: Compiled Bindings (TypedBinding) does not resubscribe to intermediary values #34428

[StephaneDelcroix]

This appears to be fixed by #34449 (backported in #34450 to release/10.0.1xx-sr5).

The reproduction here uses IsVisible="{Binding ViewModel.IsVisible}" with x:DataType="local:MainPage", where ViewModel is assigned after BindingContext = this in the constructor. With the SourceGen inflator, this produces a TypedBinding where the intermediate object (ViewModel) starts as null. When ViewModel is later set to a non-null value, the binding needs to re-subscribe to the new object's PropertyChanged — but the _isSubscribed optimization flag (now removed by #34449) was preventing that re-subscription, so changes to ViewModel.IsVisible were never picked up.

This is SourceGen-specific because only the SourceGen inflator emits TypedBinding, which had the _isSubscribed bug. The Runtime inflator uses reflection-based bindings that don't have this optimization.

[holecekp]

Is there any idea when a new version with the fix might be released? The latest one is still 10.0.50, which contains the bug.