The CommandBuffer::IssuePluginEvent(Async) seems to work fine, but once play is stopped, quitting the editor makes it unresponsive (as well as opening a new project or attaching the unity debugger)
The Visual Studio debugger writes: Your app has entered a break state, but there is no code to show because all threads were executing external code (typically system or framework code), but does on occasion show a stack trace:
[external code]
mono.dll!mono_thread_suspend_all_other_threads() Line 3412
at c:\buildslave\mono\build\mono\metadata hreads.c(3412)
mono.dll!mono_unity_jit_cleanup(_MonoDomain * domain) Line 1946
at c:\buildslave\mono\build\mono\mini\driver.c(1946)
[external code]
This is using Unity 2018.3.0b7 on windows 10 version 1809, D3D11
Thanks.