vscode-csharp: Razor intellisense doesn't work in Ubuntu 19.10

Environment data

dotnet --info output: .NET Core SDK (reflecting any global.json): Version: 3.1.100 Commit: cd82f021f4

Runtime Environment: OS Name: ubuntu OS Version: 19.10 OS Platform: Linux RID: ubuntu.19.10-x64 Base Path: /usr/share/dotnet/sdk/3.1.100/

Host (useful for support): Version: 3.1.0 Commit: 157910edee

.NET Core SDKs installed: 3.1.100 [/usr/share/dotnet/sdk]

.NET Core runtimes installed: Microsoft.AspNetCore.App 3.1.0 [/usr/share/dotnet/shared/Microsoft.AspNetCore.App] Microsoft.NETCore.App 3.1.0 [/usr/share/dotnet/shared/Microsoft.NETCore.App]

VS Code version: 1.41.1 C# Extension version: 1.21.9

Steps to reproduce

• Open Visual Studio Code

• Generate dotnet new mvc

• Try to edit .cshtml file, there should be some intellisense from Razor but there is only error: [Error - 4:38:49 AM] Request textDocument/completion failed. Message: Internal Error - System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values. (Parameter ‘index’) at Microsoft.CodeAnalysis.Text.SourceText.LineInfo.get_Item(Int32 index) at Microsoft.CodeAnalysis.Text.TextLineCollection.GetPosition(LinePosition position) at Microsoft.AspNetCore.Razor.LanguageServer.Completion.RazorCompletionEndpoint.Handle(CompletionParams request, CancellationToken cancellationToken) in /_/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/Completion/RazorCompletionEndpoint.cs:line 112 at OmniSharp.Extensions.LanguageServer.Server.Pipelines.ResolveCommandPipeline2.Handle(TRequest request, CancellationToken cancellationToken, RequestHandlerDelegate1 next) at OmniSharp.Extensions.JsonRpc.RequestRouterBase`1.RouteRequest(TDescriptor descriptor, Request request, CancellationToken token) Code: -32602

• Tried to reproduce it on Windows 10 with same versions and it works there

Expected behavior

• There should work intellisense in .cshtml file

Actual behavior

• Intellisense works only in .cs files