Caret Browsing causes app to crash on TextBlock with links

[FrayxRulez]

Describe the bug

If Caret Browsing is enabled (by pressing F7) the app will crash whenever the user tabs on a (Rich)TextBlock if it contains any Hyperlink and IsTextSelectionEnabled is set to false.

Why is this important?

Makes apps hard to use for screen reader users.
This currently accounts for more than 2.5% of crashes in my app.

Steps to reproduce the bug

1. Add a TextBlock with a Hyperlink to a Window
2. Enable Caret Browsing by pressing F7
3. Tab to focus the TextBlock

Actual behavior

No response

Expected behavior

No response

Screenshots

No response

NuGet package version

None

Windows version

No response

Additional context

This is a quite ancient bug, happens on UWP since a very long time. WinUI 3 is affected too.

[snigdha011997]

Hi @FrayxRulez , can you please provide minimal repro app for further investigation?

[FrayxRulez]

Hi @snigdha011997, it's enough to paste this in the default MainWindow.xaml:

<StackPanel Orientation="Vertical">
    <TextBlock Text="Focus this TextBlock and press F7 to enable Caret Browsing" IsTextSelectionEnabled="True" />
    <TextBlock>
        <Hyperlink>
            <Run Text="Once Caret Browsing is enabled, press Tab to focus here" />
        </Hyperlink>
    </TextBlock>
</StackPanel>

Launch the app, click on the first TextBlock and press F7, a modal about Caret Browsing will appear (it only appears if a text control is focused).
Once you enabled Caret Browsing, just tab to reach the other TextBlock, and you will see that the app will crash.

Attached a minimal repro for convenience:
CaretBrowsingRepro.zip