diff --git a/.azure/pipelines/ci.yml b/.azure/pipelines/ci.yml
index 3eec53119e41d7d2d69676c25ea7b223c4188889..7c64003843f4cd834ccf15bb3ccd7ad032528d79 100644
--- a/.azure/pipelines/ci.yml
+++ b/.azure/pipelines/ci.yml
@@ -699,8 +699,6 @@ stages:
 
   # Source build
   - job: Source_Build
-    # Skipping until someone can look into this
-    condition: false
     displayName: 'Test: Linux Source Build'
     container: centos:7
     pool:
diff --git a/eng/targets/ReferenceAssembly.targets b/eng/targets/ReferenceAssembly.targets
index 59568267bec0d6ddd5e62c78046dc334f1770610..84076d9a414ce160f00a1eac8ddc2a35f69f1c34 100644
--- a/eng/targets/ReferenceAssembly.targets
+++ b/eng/targets/ReferenceAssembly.targets
@@ -23,11 +23,14 @@
     </ItemGroup>
 
     <PropertyGroup>
+      <_TargetFrameworkOverride />
+      <_TargetFrameworkOverride
+          Condition=" @(_ResultTargetFramework->Count()) > 1 ">%0A    &lt;TargetFrameworks Condition="'%24(DotNetBuildFromSource)' == 'true'"&gt;%24(DefaultNetCoreTargetFramework)&lt;/TargetFrameworks&gt;</_TargetFrameworkOverride>
       <ProjectListContentLines><![CDATA[
 <!-- This file is automatically generated. -->
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>@(_ResultTargetFramework)</TargetFrameworks>
+    <TargetFrameworks>@(_ResultTargetFramework)</TargetFrameworks>$(_TargetFrameworkOverride)
   </PropertyGroup>
   @(ProjectListContentItem->'%(Identity)', '%0A')
 </Project>
@@ -67,7 +70,6 @@
       <_GenApiFile>$([MSBuild]::NormalizePath('$(ArtifactsDir)', 'log', 'GenAPI.rsp'))</_GenApiFile>
       <_GenAPICommand
           Condition="'$(MSBuildRuntimeType)' == 'core'">"$(DotNetTool)" --roll-forward-on-no-candidate-fx 2 "$(_GenAPIPath)"</_GenAPICommand>
-      <_GenAPICmd>$(_GenAPICommand)</_GenAPICmd>
       <_GenAPICmd>$(_GenAPICommand) @"$(_GenApiFile)"</_GenAPICmd>
       <_GenAPICmd
           Condition=" '$(AdditionalGenApiCmdOptions)' != '' ">$(_GenAPICmd) $(AdditionalGenApiCmdOptions)</_GenAPICmd>
diff --git a/src/Components/Authorization/ref/Microsoft.AspNetCore.Components.Authorization.csproj b/src/Components/Authorization/ref/Microsoft.AspNetCore.Components.Authorization.csproj
index 3a91e8a4b85b88465b91c7fe4857246b8f8332f5..53db4b90de52af317faf58c290fc390e7e59f6a0 100644
--- a/src/Components/Authorization/ref/Microsoft.AspNetCore.Components.Authorization.csproj
+++ b/src/Components/Authorization/ref/Microsoft.AspNetCore.Components.Authorization.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Components.Authorization.netstandard2.0.cs" />
diff --git a/src/Components/Components/ref/Microsoft.AspNetCore.Components.csproj b/src/Components/Components/ref/Microsoft.AspNetCore.Components.csproj
index f1aa3dab10f073a93ccb11638b6df51ca617533e..c535b143b6dbdb904bb2461ed709b3c94198da15 100644
--- a/src/Components/Components/ref/Microsoft.AspNetCore.Components.csproj
+++ b/src/Components/Components/ref/Microsoft.AspNetCore.Components.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Components.netstandard2.0.cs" />
diff --git a/src/Components/Forms/ref/Microsoft.AspNetCore.Components.Forms.csproj b/src/Components/Forms/ref/Microsoft.AspNetCore.Components.Forms.csproj
index 2ef391ee71ab29de589a3d78e89b7d1b74d6b7d0..0709f6d84b9f57fc91c571ee568115e2cb3a83d9 100644
--- a/src/Components/Forms/ref/Microsoft.AspNetCore.Components.Forms.csproj
+++ b/src/Components/Forms/ref/Microsoft.AspNetCore.Components.Forms.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Components.Forms.netstandard2.0.cs" />
diff --git a/src/Components/Web/ref/Microsoft.AspNetCore.Components.Web.csproj b/src/Components/Web/ref/Microsoft.AspNetCore.Components.Web.csproj
index 18b1e18b023acabd25f6f21e740855fc2d655b3b..bb7191613346ed7b5ac3a2f4387b2a1a52f56908 100644
--- a/src/Components/Web/ref/Microsoft.AspNetCore.Components.Web.csproj
+++ b/src/Components/Web/ref/Microsoft.AspNetCore.Components.Web.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Components.Web.netstandard2.0.cs" />
diff --git a/src/DataProtection/Abstractions/ref/Microsoft.AspNetCore.DataProtection.Abstractions.csproj b/src/DataProtection/Abstractions/ref/Microsoft.AspNetCore.DataProtection.Abstractions.csproj
index a42a893d8f9648768db4dde542cccda3d97b7cf4..a317d80c11d20d10b9ec5f944019d9484699cf13 100644
--- a/src/DataProtection/Abstractions/ref/Microsoft.AspNetCore.DataProtection.Abstractions.csproj
+++ b/src/DataProtection/Abstractions/ref/Microsoft.AspNetCore.DataProtection.Abstractions.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.DataProtection.Abstractions.netstandard2.0.cs" />
diff --git a/src/DataProtection/Cryptography.Internal/ref/Microsoft.AspNetCore.Cryptography.Internal.csproj b/src/DataProtection/Cryptography.Internal/ref/Microsoft.AspNetCore.Cryptography.Internal.csproj
index 462f2dddf5e389511326028c6cbd5cc22fe43fe6..5ea2ac05b71dd612a196d5b35d38cc7ea45ec866 100644
--- a/src/DataProtection/Cryptography.Internal/ref/Microsoft.AspNetCore.Cryptography.Internal.csproj
+++ b/src/DataProtection/Cryptography.Internal/ref/Microsoft.AspNetCore.Cryptography.Internal.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Cryptography.Internal.netstandard2.0.cs" />
diff --git a/src/DataProtection/Cryptography.KeyDerivation/ref/Microsoft.AspNetCore.Cryptography.KeyDerivation.csproj b/src/DataProtection/Cryptography.KeyDerivation/ref/Microsoft.AspNetCore.Cryptography.KeyDerivation.csproj
index dc038fa740045aa3b406e337343878785a21f921..93587ee4e041b3a3f749b9d0e8f439928e254434 100644
--- a/src/DataProtection/Cryptography.KeyDerivation/ref/Microsoft.AspNetCore.Cryptography.KeyDerivation.csproj
+++ b/src/DataProtection/Cryptography.KeyDerivation/ref/Microsoft.AspNetCore.Cryptography.KeyDerivation.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Cryptography.KeyDerivation.netstandard2.0.cs" />
diff --git a/src/DataProtection/DataProtection/ref/Microsoft.AspNetCore.DataProtection.csproj b/src/DataProtection/DataProtection/ref/Microsoft.AspNetCore.DataProtection.csproj
index 06e7d533c7d9659cc53e6efa93f70fcfa56b9904..c3d2e237c79678b5668e9b4f788d19c287fade89 100644
--- a/src/DataProtection/DataProtection/ref/Microsoft.AspNetCore.DataProtection.csproj
+++ b/src/DataProtection/DataProtection/ref/Microsoft.AspNetCore.DataProtection.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.DataProtection.netstandard2.0.cs" />
diff --git a/src/DataProtection/Extensions/ref/Microsoft.AspNetCore.DataProtection.Extensions.csproj b/src/DataProtection/Extensions/ref/Microsoft.AspNetCore.DataProtection.Extensions.csproj
index 49dd84084bc8a23ce653f0b2b43489af86829d65..df813aaf5fb3789a8ea18d3a8c13b25bf4ea9349 100644
--- a/src/DataProtection/Extensions/ref/Microsoft.AspNetCore.DataProtection.Extensions.csproj
+++ b/src/DataProtection/Extensions/ref/Microsoft.AspNetCore.DataProtection.Extensions.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.DataProtection.Extensions.netstandard2.0.cs" />
diff --git a/src/Http/Http.Features/ref/Microsoft.AspNetCore.Http.Features.csproj b/src/Http/Http.Features/ref/Microsoft.AspNetCore.Http.Features.csproj
index f2b88f0ca1ff0d357715ec2f47cbe5ef4d233df2..3009140234cde203aa4c9f458f8f81ce20d80148 100644
--- a/src/Http/Http.Features/ref/Microsoft.AspNetCore.Http.Features.csproj
+++ b/src/Http/Http.Features/ref/Microsoft.AspNetCore.Http.Features.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Http.Features.netstandard2.0.cs" />
diff --git a/src/Http/Metadata/ref/Microsoft.AspNetCore.Metadata.csproj b/src/Http/Metadata/ref/Microsoft.AspNetCore.Metadata.csproj
index 2661d12430a2d05bfcbd495cfe2f4fab33be9846..75a5dfb139e00431acc76edaeb7cdd2680442948 100644
--- a/src/Http/Metadata/ref/Microsoft.AspNetCore.Metadata.csproj
+++ b/src/Http/Metadata/ref/Microsoft.AspNetCore.Metadata.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Metadata.netstandard2.0.cs" />
diff --git a/src/Identity/Extensions.Core/ref/Microsoft.Extensions.Identity.Core.csproj b/src/Identity/Extensions.Core/ref/Microsoft.Extensions.Identity.Core.csproj
index 1fc6eeebc2e1652443d0d0661e6043ae744fdb4c..1ddecfe522d52450c1e0be3f730a992df1cdbeb0 100644
--- a/src/Identity/Extensions.Core/ref/Microsoft.Extensions.Identity.Core.csproj
+++ b/src/Identity/Extensions.Core/ref/Microsoft.Extensions.Identity.Core.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.Extensions.Identity.Core.netstandard2.0.cs" />
diff --git a/src/Identity/Extensions.Stores/ref/Microsoft.Extensions.Identity.Stores.csproj b/src/Identity/Extensions.Stores/ref/Microsoft.Extensions.Identity.Stores.csproj
index 81e68a47ceab65b9c8010000fbbfc23336c6d6d4..80d01542401acef1645f1db3ebd0a57d7cb23d7b 100644
--- a/src/Identity/Extensions.Stores/ref/Microsoft.Extensions.Identity.Stores.csproj
+++ b/src/Identity/Extensions.Stores/ref/Microsoft.Extensions.Identity.Stores.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.Extensions.Identity.Stores.netstandard2.0.cs" />
diff --git a/src/Security/Authorization/Core/ref/Microsoft.AspNetCore.Authorization.csproj b/src/Security/Authorization/Core/ref/Microsoft.AspNetCore.Authorization.csproj
index b0cf327ff4645f103603a832a2d575b949e826aa..b4543827dab281948868aa2f90f966fb488eebae 100644
--- a/src/Security/Authorization/Core/ref/Microsoft.AspNetCore.Authorization.csproj
+++ b/src/Security/Authorization/Core/ref/Microsoft.AspNetCore.Authorization.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Authorization.netstandard2.0.cs" />
diff --git a/src/Servers/Connections.Abstractions/ref/Directory.Build.targets b/src/Servers/Connections.Abstractions/ref/Directory.Build.targets
deleted file mode 100644
index 1c2059ecd04460830a828dbc08e3e6955f09ad95..0000000000000000000000000000000000000000
--- a/src/Servers/Connections.Abstractions/ref/Directory.Build.targets
+++ /dev/null
@@ -1,7 +0,0 @@
-<Project>
-  <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory)..\, Directory.Build.targets))\Directory.Build.targets" />
-
-  <PropertyGroup>
-    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
-  </PropertyGroup>
-</Project>
\ No newline at end of file
diff --git a/src/Servers/Connections.Abstractions/ref/Microsoft.AspNetCore.Connections.Abstractions.csproj b/src/Servers/Connections.Abstractions/ref/Microsoft.AspNetCore.Connections.Abstractions.csproj
index c6a77eb8ef10905166c6ef14b1289feb7bcf907d..3451731fed039949d5ac298b9c48dbe7cd5c876c 100644
--- a/src/Servers/Connections.Abstractions/ref/Microsoft.AspNetCore.Connections.Abstractions.csproj
+++ b/src/Servers/Connections.Abstractions/ref/Microsoft.AspNetCore.Connections.Abstractions.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;netstandard2.1;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Connections.Abstractions.netstandard2.0.cs" />
diff --git a/src/SignalR/common/Http.Connections.Common/ref/Microsoft.AspNetCore.Http.Connections.Common.csproj b/src/SignalR/common/Http.Connections.Common/ref/Microsoft.AspNetCore.Http.Connections.Common.csproj
index 8ae1a927db91b30e75d993b734a2d85db14218d0..83ec067e2074aee42b6bff09864fa3d6fa46d8f6 100644
--- a/src/SignalR/common/Http.Connections.Common/ref/Microsoft.AspNetCore.Http.Connections.Common.csproj
+++ b/src/SignalR/common/Http.Connections.Common/ref/Microsoft.AspNetCore.Http.Connections.Common.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.Http.Connections.Common.netstandard2.0.cs" />
diff --git a/src/SignalR/common/Protocols.Json/ref/Microsoft.AspNetCore.SignalR.Protocols.Json.csproj b/src/SignalR/common/Protocols.Json/ref/Microsoft.AspNetCore.SignalR.Protocols.Json.csproj
index 19480b336fb99e24eb2e6252e3a3dab0e8a64d31..e437919dfb214556a83970eb2cedd282bdfb8667 100644
--- a/src/SignalR/common/Protocols.Json/ref/Microsoft.AspNetCore.SignalR.Protocols.Json.csproj
+++ b/src/SignalR/common/Protocols.Json/ref/Microsoft.AspNetCore.SignalR.Protocols.Json.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.SignalR.Protocols.Json.netstandard2.0.cs" />
diff --git a/src/SignalR/common/SignalR.Common/ref/Microsoft.AspNetCore.SignalR.Common.csproj b/src/SignalR/common/SignalR.Common/ref/Microsoft.AspNetCore.SignalR.Common.csproj
index ce6ebe8ce1bef68d1d158996570a391c3119752c..b1ad909f3425aa84e01bbee6653c23c1780ca9cc 100644
--- a/src/SignalR/common/SignalR.Common/ref/Microsoft.AspNetCore.SignalR.Common.csproj
+++ b/src/SignalR/common/SignalR.Common/ref/Microsoft.AspNetCore.SignalR.Common.csproj
@@ -2,6 +2,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>netstandard2.0;$(DefaultNetCoreTargetFramework)</TargetFrameworks>
+    <TargetFrameworks Condition="'$(DotNetBuildFromSource)' == 'true'">$(DefaultNetCoreTargetFramework)</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
     <Compile Include="Microsoft.AspNetCore.SignalR.Common.netstandard2.0.cs" />