Hi,
Using React.NET 3.0.1 which uses ClearScript.V8 5.4.8 following hang is observed on recycling application pool
```
.NET Call Stack
.SharedPtr.Release(SharedPtr*)+d7
[[InlinedCallFrame] (.Decrement)] .RefCount.Decrement(RefCount*)
Microsoft.ClearScript.V8.V8ContextProxyImpl.!V8ContextProxyImpl()+4e
Microsoft.ClearScript.V8.V8ContextProxyImpl.Dispose(Boolean)+1f
[[DebuggerU2MCatchHandlerFrame]]
[[ContextTransitionFrame]]
[[GCFrame]]
[[DebuggerU2MCatchHandlerFrame]]
Full Call Stack
ntdll!NtWaitForSingleObject+14
KERNELBASE!WaitForSingleObjectEx+8f
v8_x64!v8::Extension::dependencies+329ac
v8_x64!v8::ExternalResourceVisitor::VisitExternalString+28187
v8_x64!v8::ExternalResourceVisitor::VisitExternalString+1a3
v8_x64!v8::ExternalResourceVisitor::VisitExternalString+533b
ClearScriptV8_64+14216
ClearScriptV8_64+120e4
ClearScriptV8_64+13e3f
ClearScriptV8_64+50a8
<Module>.SharedPtr<V8Context>.Release(SharedPtr<V8Context>*)+d7
[[InlinedCallFrame] (<Module>.Decrement)] <Module>.RefCount.Decrement(RefCount*)
Microsoft.ClearScript.V8.V8ContextProxyImpl.!V8ContextProxyImpl()+4e
Microsoft.ClearScript.V8.V8ContextProxyImpl.Dispose(Boolean)+1f
clr!FastCallFinalizeWorker+6
clr!ETW::GCLog::SendFinalizeObjectEvent+c9
clr!MethodTable::CallFinalizer+b5
clr!CallFinalizer+5e
clr!FinalizerThread::DoOneFinalization+95
clr!FinalizerThread::FinalizeAllObjects+133
clr!FinalizerThread::FinalizeAllObjects_Wrapper+18
clr!Frame::Push+59
clr!PEDecoder::GetNativeCodeManagerTable+170
clr!PEDecoder::GetNativeCodeManagerTable+99
[[DebuggerU2MCatchHandlerFrame]]
clr!Thread::ShouldChangeAbortToUnload+45
clr!Thread::DoADCallBack+109
[[ContextTransitionFrame]]
clr!Frame::Push+a2
clr!FinalizerThread::DoOneFinalization+1f9
[[GCFrame]]
clr!FinalizerThread::FinalizeAllObjects+133
clr!FinalizerThread::FinalizerThreadWorker+bb
clr!Frame::Push+59
clr!PEDecoder::GetNativeCodeManagerTable+170
clr!PEDecoder::GetNativeCodeManagerTable+99
[[DebuggerU2MCatchHandlerFrame]]
clr!FinalizerThread::FinalizerThreadStart+10a
clr!Thread::intermediateThreadProc+86
kernel32!BaseThreadInitThunk+14
ntdll!RtlUserThreadStart+21
```
Comments: It seems indefinitely to me. Last time it was hanging for about an hour before I've killed w3wp process.
Using React.NET 3.0.1 which uses ClearScript.V8 5.4.8 following hang is observed on recycling application pool
```
.NET Call Stack
.SharedPtr.Release(SharedPtr*)+d7
[[InlinedCallFrame] (.Decrement)] .RefCount.Decrement(RefCount*)
Microsoft.ClearScript.V8.V8ContextProxyImpl.!V8ContextProxyImpl()+4e
Microsoft.ClearScript.V8.V8ContextProxyImpl.Dispose(Boolean)+1f
[[DebuggerU2MCatchHandlerFrame]]
[[ContextTransitionFrame]]
[[GCFrame]]
[[DebuggerU2MCatchHandlerFrame]]
Full Call Stack
ntdll!NtWaitForSingleObject+14
KERNELBASE!WaitForSingleObjectEx+8f
v8_x64!v8::Extension::dependencies+329ac
v8_x64!v8::ExternalResourceVisitor::VisitExternalString+28187
v8_x64!v8::ExternalResourceVisitor::VisitExternalString+1a3
v8_x64!v8::ExternalResourceVisitor::VisitExternalString+533b
ClearScriptV8_64+14216
ClearScriptV8_64+120e4
ClearScriptV8_64+13e3f
ClearScriptV8_64+50a8
<Module>.SharedPtr<V8Context>.Release(SharedPtr<V8Context>*)+d7
[[InlinedCallFrame] (<Module>.Decrement)] <Module>.RefCount.Decrement(RefCount*)
Microsoft.ClearScript.V8.V8ContextProxyImpl.!V8ContextProxyImpl()+4e
Microsoft.ClearScript.V8.V8ContextProxyImpl.Dispose(Boolean)+1f
clr!FastCallFinalizeWorker+6
clr!ETW::GCLog::SendFinalizeObjectEvent+c9
clr!MethodTable::CallFinalizer+b5
clr!CallFinalizer+5e
clr!FinalizerThread::DoOneFinalization+95
clr!FinalizerThread::FinalizeAllObjects+133
clr!FinalizerThread::FinalizeAllObjects_Wrapper+18
clr!Frame::Push+59
clr!PEDecoder::GetNativeCodeManagerTable+170
clr!PEDecoder::GetNativeCodeManagerTable+99
[[DebuggerU2MCatchHandlerFrame]]
clr!Thread::ShouldChangeAbortToUnload+45
clr!Thread::DoADCallBack+109
[[ContextTransitionFrame]]
clr!Frame::Push+a2
clr!FinalizerThread::DoOneFinalization+1f9
[[GCFrame]]
clr!FinalizerThread::FinalizeAllObjects+133
clr!FinalizerThread::FinalizerThreadWorker+bb
clr!Frame::Push+59
clr!PEDecoder::GetNativeCodeManagerTable+170
clr!PEDecoder::GetNativeCodeManagerTable+99
[[DebuggerU2MCatchHandlerFrame]]
clr!FinalizerThread::FinalizerThreadStart+10a
clr!Thread::intermediateThreadProc+86
kernel32!BaseThreadInitThunk+14
ntdll!RtlUserThreadStart+21
```
Comments: It seems indefinitely to me. Last time it was hanging for about an hour before I've killed w3wp process.