Text Block displays incorrect TextAlignment after changing property

[renrutsirhc]

Describe the bug

A Text Block with TextAlignment set to Center/Right (possibly others) can get into a state where although the TextBlock's TextAlignment property is still set correctly, the visual appearance of the TextBlock is TextAlignment left. This seems to happen only in certain cases:

• When changing the font from a ComboBox (tested using standard Fluent theme and FluentAvalonia theme)
• When changing the font color from a Fluent Avalonia ColorPickerButton when approving the color with a button (tested using FluentAvalonia theme) ColorPickerButton change color causes TextAlignment to be incorrectly displayed in a TextBlock amwx/FluentAvalonia#647
• Possibly related? - TextAlignment wrong when switching theme from within a CommandBar secondary command amwx/FluentAvalonia#637

Screen.Recording.2025-02-06.083019.mp4

To Reproduce

• TextBlock with TextAlignment set to Right and FontFamily bound to Font on the VM
• ComboBox with SelectedItem Bound to Font on VM
• Change the font using the combobox
• Observe change of visual TextAlignment

Minimal repro: TextAlignmentRepro.zip

Expected behavior

TextBlock should display it's text aligned correctly.

Avalonia version

11.2.3

OS

Windows

Additional context

No response

[timunie]

Nightly reproduces this issue. After resizing the window the text is rendered as it should be.

[renrutsirhc]

After being incorrectly rendered, the text also gets rendered as it should be if you change the FontWeight or change the TextAlignment properties.