Red squigglies in all razor pages in latest update (2.28.11)

[lonix1]

Environment data

dotnet --info output: 7.0.18
VS Code version: 1.89.0 (latest)
C# Extension version: 2.28.11 (latest)

OmniSharp log

n/a

Steps to reproduce

I just updated to the latest extension, offered a few hours ago.

Now all my razor pages show red squigglies, even though they compile correctly and the app runs without error.

The red squigglies make this version completely unusable so I intend to roll back to a previous version.

Expected behavior

No squigglies.

Actual behavior

Squigglies.

Additional context

Here's an example from one of many razor (Foo.cshtml) files:

Ambiguity between 'Pages_Customers_Orders_Index.__Microsoft_AspNetCore_Mvc_TagHelpers_FormTagHelper' and 'Pages_Customers_Orders_Index.__Microsoft_AspNetCore_Mvc_TagHelpers_FormTagHelper'CS0229
Ambiguity between 'Pages_Customers_Orders_Index.__tagHelperRunner' and 'Pages_Customers_Orders_Index.__tagHelperRunner'CS0229
Ambiguity between 'Pages_Customers_Orders_Index.__tagHelperExecutionContext' and 'Pages_Customers_Orders_Index.__tagHelperExecutionContext'CS0229
Ambiguity between 'Pages_Customers_Orders_Index.__Microsoft_AspNetCore_Mvc_TagHelpers_FormTagHelper' and 'Pages_Customers_Orders_Index.__Microsoft_AspNetCore_Mvc_TagHelpers_FormTagHelper'CS0229

[phil-allen-msft]

@lonix1 , we're sorry you are running into this. We noticed the same recently and are already working on it, and we'll keep you (and others who run into it) posted here.

[lonix1]

@phil-allen-msft NP these things happen. My fault for being an early adopter! :-)

[jeffnyalik]

Same problem here:
Ambiguity between 'Pages_Movies_index.__Microsoft_AspNetCore_Mvc_TagHelpers_AnchorTagHelper. Any work around it is so annoying.

[davidwengier]

@jeffnyalik you should be able to roll back to the previous version of the extension in VS Code, using the "Install specific version" dropdown

[jeffnyalik]

@davidwengier I have rolled back to the previous version and the red squiggly still persist. Here is the extension am using:
https://github.com/KreativJos/csharpextensions

[lonix1]

I rolled back to the previous version (2.23.15) and the problem disappeared. You probably have a different issue.

[jeffnyalik]

Thanks @Ionix1 and @davidwengier rolling back C# for Visual Studio Code to version 2.23.15 solved the issue.

[phil-allen-msft]

Update: We understand what caused the issue, we understand why it didn't occur before, and have a plan to fix it. We'll keep you posted here.

[ryzngard]

Fix has been merged into prerelease in vscode with dotnet/vscode-csharp#7134

[lonix1]

To anyone who lands here, don't upgrade to v2.30.28 either. I guess the fix will be in the version after that.

Stay on 2.23.15 for now.

[lonix1]

Just installed 2.31.19. Problem RESOLVED! Thanks.