vscode-csharp: Problems loading Unity project

Environment data

dotnet --info output:

.NET SDK (reflecting any global.json):
 Version:   5.0.103
 Commit:    72dec52dbd

Runtime Environment:
 OS Name:     arch
 OS Version:  
 OS Platform: Linux
 RID:         arch-x64
 Base Path:   /usr/share/dotnet/sdk/5.0.103/

Host (useful for support):
  Version: 5.0.3
  Commit:  c636bbdc8a

.NET SDKs installed:
  2.1.813 [/usr/share/dotnet/sdk]
  2.2.110 [/usr/share/dotnet/sdk]
  3.1.108 [/usr/share/dotnet/sdk]
  5.0.103 [/usr/share/dotnet/sdk]

.NET runtimes installed:
  Microsoft.NETCore.App 2.1.25 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.2.8 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.8 [/usr/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.3 [/usr/share/dotnet/shared/Microsoft.NETCore.App]

To install additional .NET runtimes or SDKs:
  https://aka.ms/dotnet-download

VS Code version: 1.53.2

C# Extension version: v1.23.9

OmniSharp log

Starting OmniSharp server at 2/23/2021, 10:53:57 PM
    Target: /home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/test.sln

OmniSharp server started with Mono 6.12.0.
    Path: /home/jirka/.vscode/extensions/ms-dotnettools.csharp-1.23.9/.omnisharp/1.37.6/omnisharp/OmniSharp.exe
    PID: 1010195

[info]: OmniSharp.Stdio.Host
        Starting OmniSharp on arch 0.0 (x64)
[info]: OmniSharp.Services.DotNetCliService
        DotNetPath set to dotnet
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        Located 2 MSBuild instance(s)
            1: Mono 16.8.0 - "/usr/lib/mono/msbuild/Current/bin"
            2: StandAlone 16.8.0 - "/home/jirka/.vscode/extensions/ms-dotnettools.csharp-1.23.9/.omnisharp/1.37.6/omnisharp/.msbuild/Current/Bin"
[warn]: OmniSharp.CompositionHostBuilder
        It looks like you have Visual Studio 2019 installed without .NET Core SDK support which is required by OmniSharp.
 Try updating Visual Studio 2019 installation with .NET Core SDK to enable better MSBuild support.
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        MSBUILD_EXE_PATH environment variable set to '/home/jirka/.vscode/extensions/ms-dotnettools.csharp-1.23.9/.omnisharp/1.37.6/omnisharp/.msbuild/Current/Bin/MSBuild.exe'
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        Registered MSBuild instance: StandAlone 16.8.0 - "/home/jirka/.vscode/extensions/ms-dotnettools.csharp-1.23.9/.omnisharp/1.37.6/omnisharp/.msbuild/Current/Bin"
            CscToolExe = csc.exe
            MSBuildToolsPath = /home/jirka/.vscode/extensions/ms-dotnettools.csharp-1.23.9/.omnisharp/1.37.6/omnisharp/.msbuild/Current/Bin
            CscToolPath = /home/jirka/.vscode/extensions/ms-dotnettools.csharp-1.23.9/.omnisharp/1.37.6/omnisharp/.msbuild/Current/Bin/Roslyn
            BypassFrameworkInstallChecks = true
            MSBuildExtensionsPath = /home/jirka/.vscode/extensions/ms-dotnettools.csharp-1.23.9/.omnisharp/1.37.6/omnisharp/.msbuild
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.CSharpFormattingWorkspaceOptionsProvider, Order: 0
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.Completion.CompletionOptionsProvider, Order: 0
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.RenameWorkspaceOptionsProvider, Order: 100
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.ImplementTypeWorkspaceOptionsProvider, Order: 110
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.BlockStructureWorkspaceOptionsProvider, Order: 140
[info]: OmniSharp.Cake.CakeProjectSystem
        Detecting Cake files in '/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test'.
[info]: OmniSharp.Cake.CakeProjectSystem
        Could not find any Cake files
[info]: OmniSharp.MSBuild.ProjectSystem
        Detecting projects in '/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/test.sln'.
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Assembly-CSharp.csproj'
[info]: OmniSharp.Script.ScriptProjectSystem
        Detecting CSX files in '/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test'.
[info]: OmniSharp.Script.ScriptProjectSystem
        Could not find any CSX files
[info]: OmniSharp.WorkspaceInitializer
        Configuration finished.
[info]: OmniSharp.Stdio.Host
        Omnisharp server running using Stdio at location '/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test' on host 1009992.
[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Assembly-CSharp.csproj
Can't find custom attr constructor image: /home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Library/ScriptAssemblies/Unity.Rider.Editor.dll mtoken: 0x0a000007 due to: Could not find method '.ctor' due to a type load error: Could not set up parent class, due to: Could not set up parent class, due to:  assembly:/home/jirka/Programs/Unity/Editor/2019.4.20f1/Editor/Data/NetStandard/ref/2.0.0/netstandard.dll type:Object member:(null) assembly:/home/jirka/Programs/Unity/Editor/2019.4.20f1/Editor/Data/NetStandard/ref/2.0.0/netstandard.dll type:Attribute member:(null) assembly:/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Library/ScriptAssemblies/UnityEngine.TestRunner.dll type:TestRunCallbackAttribute member:(null) assembly:/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Library/ScriptAssemblies/UnityEngine.TestRunner.dll type:TestRunCallbackAttribute member:(null)
[fail]: OmniSharp.MSBuild.ProjectLoader
        The "ResolveAssemblyReference" task failed unexpectedly.
System.TypeLoadException: Could not find method '.ctor' due to a type load error: Could not set up parent class, due to: Could not set up parent class, due to:  assembly:/home/jirka/Programs/Unity/Editor/2019.4.20f1/Editor/Data/NetStandard/ref/2.0.0/netstandard.dll type:Object member:(null) assembly:/home/jirka/Programs/Unity/Editor/2019.4.20f1/Editor/Data/NetStandard/ref/2.0.0/netstandard.dll type:Attribute member:(null) assembly:/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Library/ScriptAssemblies/UnityEngine.TestRunner.dll type:TestRunCallbackAttribute member:(null)
  at (wrapper managed-to-native) System.MonoCustomAttrs.GetCustomAttributesDataInternal(System.Reflection.ICustomAttributeProvider)
  at System.MonoCustomAttrs.GetCustomAttributesDataBase (System.Reflection.ICustomAttributeProvider obj, System.Type attributeType, System.Boolean inheritedOnly) [0x00010] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at System.MonoCustomAttrs.GetCustomAttributesData (System.Reflection.ICustomAttributeProvider obj, System.Boolean inherit) [0x00011] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at System.Reflection.CustomAttributeData.GetCustomAttributes (System.Reflection.Assembly target) [0x00000] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at System.Reflection.RuntimeAssembly.GetCustomAttributesData () [0x00000] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at Microsoft.Build.Tasks.AssemblyInformation.GetFrameworkName () [0x00025] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.AssemblyInformation.get_FrameworkNameAttribute () [0x00028] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.AssemblyDependency.AssemblyMetadata..ctor (System.String path) [0x00019] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.AssemblyInformation+<>c.<GetAssemblyMetadata>b__21_0 (System.String p) [0x00000] in <284d11f275764cafba668d0e682555f7>:0 
  at System.Collections.Concurrent.ConcurrentDictionary`2[TKey,TValue].GetOrAdd (TKey key, System.Func`2[T,TResult] valueFactory) [0x00034] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at Microsoft.Build.Tasks.AssemblyInformation.GetAssemblyMetadata (System.String path, System.Collections.Concurrent.ConcurrentDictionary`2[TKey,TValue] assemblyMetadataCache, Microsoft.Build.Shared.AssemblyNameExtension[]& dependencies, System.String[]& scatterFiles, System.Runtime.Versioning.FrameworkName& frameworkName) [0x00006] in <284d11f275764cafba668d0e682555f7>:0 
  at (wrapper delegate-invoke) <Module>.invoke_void_string_ConcurrentDictionary`2<string, AssemblyMetadata>_AssemblyNameExtension[]&_string[]&_FrameworkName&(string,System.Collections.Concurrent.ConcurrentDictionary`2<string, Microsoft.Build.Tasks.AssemblyDependency.AssemblyMetadata>,Microsoft.Build.Shared.AssemblyNameExtension[]&,string[]&,System.Runtime.Versioning.FrameworkName&)
  at Microsoft.Build.Tasks.SystemState.GetAssemblyMetadata (System.String path, System.Collections.Concurrent.ConcurrentDictionary`2[TKey,TValue] assemblyMetadataCache, Microsoft.Build.Shared.AssemblyNameExtension[]& dependencies, System.String[]& scatterFiles, System.Runtime.Versioning.FrameworkName& frameworkName) [0x00010] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.GetUnifiedAssemblyMetadata (Microsoft.Build.Tasks.Reference reference, System.Collections.Generic.IEnumerable`1[Microsoft.Build.Tasks.UnifiedAssemblyName]& unifiedDependencies, System.String[]& scatterFiles) [0x00023] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.FindDependenciesAndScatterFiles (Microsoft.Build.Tasks.Reference reference, System.Collections.Generic.List`1[T] newEntries) [0x0003a] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.FindAssociatedFiles () [0x000ea] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.ComputeClosure () [0x0000a] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.ComputeClosure (System.Collections.Generic.IEnumerable`1[T] remappedAssembliesValue, Microsoft.Build.Framework.ITaskItem[] referenceAssemblyFiles, Microsoft.Build.Framework.ITaskItem[] referenceAssemblyNames, System.Collections.Generic.List`1[T] exceptions) [0x00038] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ResolveAssemblyReference.Execute (Microsoft.Build.Shared.FileExists fileExists, Microsoft.Build.Shared.DirectoryExists directoryExists, Microsoft.Build.Tasks.GetDirectories getDirectories, Microsoft.Build.Tasks.GetAssemblyName getAssemblyName, Microsoft.Build.Tasks.GetAssemblyMetadata getAssemblyMetadata, Microsoft.Build.Shared.GetRegistrySubKeyNames getRegistrySubKeyNames, Microsoft.Build.Shared.GetRegistrySubKeyDefaultValue getRegistrySubKeyDefaultValue, Microsoft.Build.Tasks.GetLastWriteTime getLastWriteTime, Microsoft.Build.Tasks.GetAssemblyRuntimeVersion getRuntimeVersion, Microsoft.Build.Shared.OpenBaseKey openBaseKey, Microsoft.Build.Tasks.GetAssemblyPathInGac getAssemblyPathInGac, Microsoft.Build.Tasks.IsWinMDFile isWinMDFile, Microsoft.Build.Tasks.ReadMachineTypeFromPEHeader readMachineTypeFromPEHeader) [0x00515] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ResolveAssemblyReference.Execute () [0x00000] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute () [0x00029] in <f7274894ce154696afba1f0ffcd06434>:0 
  at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask (Microsoft.Build.BackEnd.ITaskExecutionHost taskExecutionHost, Microsoft.Build.BackEnd.Logging.TaskLoggingContext taskLoggingContext, Microsoft.Build.BackEnd.TaskHost taskHost, Microsoft.Build.BackEnd.ItemBucket bucket, Microsoft.Build.BackEnd.TaskExecutionMode howToExecuteTask) [0x002fc] in <f7274894ce154696afba1f0ffcd06434>:0 
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Assembly-CSharp.csproj'.
/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Assembly-CSharp.csproj
/home/jirka/.vscode/extensions/ms-dotnettools.csharp-1.23.9/.omnisharp/1.37.6/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(2123,5): Error: The "ResolveAssemblyReference" task failed unexpectedly.
System.TypeLoadException: Could not find method '.ctor' due to a type load error: Could not set up parent class, due to: Could not set up parent class, due to:  assembly:/home/jirka/Programs/Unity/Editor/2019.4.20f1/Editor/Data/NetStandard/ref/2.0.0/netstandard.dll type:Object member:(null) assembly:/home/jirka/Programs/Unity/Editor/2019.4.20f1/Editor/Data/NetStandard/ref/2.0.0/netstandard.dll type:Attribute member:(null) assembly:/home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Library/ScriptAssemblies/UnityEngine.TestRunner.dll type:TestRunCallbackAttribute member:(null)
  at (wrapper managed-to-native) System.MonoCustomAttrs.GetCustomAttributesDataInternal(System.Reflection.ICustomAttributeProvider)
  at System.MonoCustomAttrs.GetCustomAttributesDataBase (System.Reflection.ICustomAttributeProvider obj, System.Type attributeType, System.Boolean inheritedOnly) [0x00010] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at System.MonoCustomAttrs.GetCustomAttributesData (System.Reflection.ICustomAttributeProvider obj, System.Boolean inherit) [0x00011] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at System.Reflection.CustomAttributeData.GetCustomAttributes (System.Reflection.Assembly target) [0x00000] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at System.Reflection.RuntimeAssembly.GetCustomAttributesData () [0x00000] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at Microsoft.Build.Tasks.AssemblyInformation.GetFrameworkName () [0x00025] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.AssemblyInformation.get_FrameworkNameAttribute () [0x00028] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.AssemblyDependency.AssemblyMetadata..ctor (System.String path) [0x00019] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.AssemblyInformation+<>c.<GetAssemblyMetadata>b__21_0 (System.String p) [0x00000] in <284d11f275764cafba668d0e682555f7>:0 
  at System.Collections.Concurrent.ConcurrentDictionary`2[TKey,TValue].GetOrAdd (TKey key, System.Func`2[T,TResult] valueFactory) [0x00034] in <efe941bb62534dc3a62ceb1a818964a0>:0 
  at Microsoft.Build.Tasks.AssemblyInformation.GetAssemblyMetadata (System.String path, System.Collections.Concurrent.ConcurrentDictionary`2[TKey,TValue] assemblyMetadataCache, Microsoft.Build.Shared.AssemblyNameExtension[]& dependencies, System.String[]& scatterFiles, System.Runtime.Versioning.FrameworkName& frameworkName) [0x00006] in <284d11f275764cafba668d0e682555f7>:0 
  at (wrapper delegate-invoke) <Module>.invoke_void_string_ConcurrentDictionary`2<string, AssemblyMetadata>_AssemblyNameExtension[]&_string[]&_FrameworkName&(string,System.Collections.Concurrent.ConcurrentDictionary`2<string, Microsoft.Build.Tasks.AssemblyDependency.AssemblyMetadata>,Microsoft.Build.Shared.AssemblyNameExtension[]&,string[]&,System.Runtime.Versioning.FrameworkName&)
  at Microsoft.Build.Tasks.SystemState.GetAssemblyMetadata (System.String path, System.Collections.Concurrent.ConcurrentDictionary`2[TKey,TValue] assemblyMetadataCache, Microsoft.Build.Shared.AssemblyNameExtension[]& dependencies, System.String[]& scatterFiles, System.Runtime.Versioning.FrameworkName& frameworkName) [0x00010] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.GetUnifiedAssemblyMetadata (Microsoft.Build.Tasks.Reference reference, System.Collections.Generic.IEnumerable`1[Microsoft.Build.Tasks.UnifiedAssemblyName]& unifiedDependencies, System.String[]& scatterFiles) [0x00023] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.FindDependenciesAndScatterFiles (Microsoft.Build.Tasks.Reference reference, System.Collections.Generic.List`1[T] newEntries) [0x0003a] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.FindAssociatedFiles () [0x000ea] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.ComputeClosure () [0x0000a] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ReferenceTable.ComputeClosure (System.Collections.Generic.IEnumerable`1[T] remappedAssembliesValue, Microsoft.Build.Framework.ITaskItem[] referenceAssemblyFiles, Microsoft.Build.Framework.ITaskItem[] referenceAssemblyNames, System.Collections.Generic.List`1[T] exceptions) [0x00038] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ResolveAssemblyReference.Execute (Microsoft.Build.Shared.FileExists fileExists, Microsoft.Build.Shared.DirectoryExists directoryExists, Microsoft.Build.Tasks.GetDirectories getDirectories, Microsoft.Build.Tasks.GetAssemblyName getAssemblyName, Microsoft.Build.Tasks.GetAssemblyMetadata getAssemblyMetadata, Microsoft.Build.Shared.GetRegistrySubKeyNames getRegistrySubKeyNames, Microsoft.Build.Shared.GetRegistrySubKeyDefaultValue getRegistrySubKeyDefaultValue, Microsoft.Build.Tasks.GetLastWriteTime getLastWriteTime, Microsoft.Build.Tasks.GetAssemblyRuntimeVersion getRuntimeVersion, Microsoft.Build.Shared.OpenBaseKey openBaseKey, Microsoft.Build.Tasks.GetAssemblyPathInGac getAssemblyPathInGac, Microsoft.Build.Tasks.IsWinMDFile isWinMDFile, Microsoft.Build.Tasks.ReadMachineTypeFromPEHeader readMachineTypeFromPEHeader) [0x00515] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.Tasks.ResolveAssemblyReference.Execute () [0x00000] in <284d11f275764cafba668d0e682555f7>:0 
  at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute () [0x00029] in <f7274894ce154696afba1f0ffcd06434>:0 
  at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask (Microsoft.Build.BackEnd.ITaskExecutionHost taskExecutionHost, Microsoft.Build.BackEnd.Logging.TaskLoggingContext taskLoggingContext, Microsoft.Build.BackEnd.TaskHost taskHost, Microsoft.Build.BackEnd.ItemBucket bucket, Microsoft.Build.BackEnd.TaskExecutionMode howToExecuteTask) [0x002fc] in <f7274894ce154696afba1f0ffcd06434>:0 

[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /home/jirka/Programs/Projects/Unity/LearnUnity/FirstTry/test/Assembly-CSharp.csproj

Steps to reproduce

Create any project using Unity hub, in Unity editor create New C# script, open it in visual studio code

Expected behavior

Loading the project correctly and working intelisense

Actual behavior

The project fails to load and intelisense is not working