Error using RichTextBox control with right-aligned bullets on Windows 11 24H2

[Nora-Zhou01]

.NET version

10.0.100-alpha.1.24573.1

Did it work in .NET Framework?

Yes

Did it work in any of the earlier releases of .NET Core or .NET 5+?

No, repro in .NET 8.0

Issue description

Error using RichTextBox control with right-aligned bullets on Windows 11 24H2

Windows 11 Enterprise 24H2

24H2.mp4

.NET 10 (.NET 9.0 with the same results)

.NET 8

Windows 11 Enterprise 23H2

23H2.mp4

Steps to reproduce

1. Create a Winforms .Net Core application and add RichTextBox and Button controls
2. Set the Text of the RichTextBox to test
3. Double-click the Button and add the following code

this.richTextBox1.Text = "test";

richTextBox1.RightToLeft = RightToLeft.Yes;

richTextBox1.SelectionBullet = true;

5. Run the project on both Windows 11 23H2 and 24H2

Or

1. Launch the WinFormsApp5.zip project
2. Run the project on both Windows 11 23H2 and 24H2

More Info:
The issue is from customer feedback ticket: https://devdiv.visualstudio.com/DevDiv/_workitems/edit/2316184

[sohailaboebs]

I have almost the same issue, below is a description of what I had:
I am using Windows 11 and Microsoft Visual Studio to [C# Windows Forms] applications
I have a RichTextBox control that has rich text inside it
After updating to Windows 11 [24H2] I had an issue with filling the rich text box with text, below are the steps that cause the issue:

Start Visual Studio[Microsoft Visual Studio Community 2022 (64-bit) - Current]
Create a Windows Forms Application and Use .Net 8.0
Add a rich text box to the form
Add a button and put the code below in the button event handler:
private void button2_Click(object sender, EventArgs e)
{
this.richTextBox1.Text = “This is a test”;
richTextBox1.RightToLeft = RightToLeft.Yes;
richTextBox1.SelectionBullet = true;
}
You will get the exception below:
System.AccessViolationException: ‘Attempted to read or write protected memory. This is often an indication that other memory is corrupt.’
Rolling back to [23H2] clears this issue, please solve this bug

For my issue it looks like something went wrong when my Windows 11 updated to "Windows 11 [24H2]", almost on the same day or around it Visual Studio also had an update, one of these updates caused this issue, rolling back to "Windows 11 [23H2]" cleared this issue, the issue is related to the update, I am using [.Net 8.0] and I am using [Windows Forms and C#]
Thank you

[merriemcgaw]

@Nora-Zhou01 , does this happen in Framework on the same Win11 builds? Is there a .NET release where it did work? We'd also like to see if this happens in MFC apps. Is there other formatting where this has the exception (numbered, bold, italics) ?

[Nora-Zhou01]

@Nora-Zhou01 , does this happen in Framework on the same Win11 builds?
Is there a .NET release where it did work? We'd also like to see if this happens in MFC apps. Is there other formatting where this has the exception (numbered, bold, italics) ?

Does not repro in the same Win11 24H2 version of the Framework and MFC project. The issue does not repro when setting other formats of the RichTextBox. I tried VS2019 16.5 and this issue still repro.

[merriemcgaw]

@LeafShi1 can your team investigate any differences in how we interact with the MFC control between NetFX and Core, or between MFC and Core? That should point us in the right direction.

[merriemcgaw]

@Nora-Zhou01 I want to confirm that you aren't seeing this on earlier versions of Win11 just the latest?

[Nora-Zhou01]

@Nora-Zhou01 I want to confirm that you aren't seeing this on earlier versions of Win11 just the latest?

This issue only occurs in win11 24h2 OS, and other versions do not reproduce

[LeafShi1]

@LeafShi1 can your team investigate any differences in how we interact with the MFC control between NetFX and Core, or between MFC and Core? That should point us in the right direction.

There is no difference between the way NetFX and Core interact with MFC controls, except for the way messages are sent.
Core uses PInvokeCore.SendMessage(this, PInvokeCore.EM_SETPARAFORMAT, 0, ref pf);
And NetFX uses UnsafeNativeMethods.SendMessage(new HandleRef(this, base.Handle), 1095, 0, pARAFORMAT);
But this is not the cause of this issue.

And the property SelectionBullet itself has no problem. This issue must be reproduced by setting richTextBox1.RightToLeft = RightToLeft.Yes; and then setting richTextBox1.SelectionBullet = true; and in win11 24h2 OS.
In the MFC project, RichTextBox does not have a property corresponding to RightToLeft, so this issue cannot be reproduced.