Today I helped my colleague to pinpoint deadlock cause in VS2015 project
It was 30 seconds debug session.
The first 10 seconds were as following:

But I think this feature seems to be lost for VS2019 .

What is more concerning, looks like it cannot be implemented for <shared_mutex>, since it is SRWLOCK based.

And I expect that vNext <mutex> will be the same, as I think it should be either SRWLOCK based or atomic wait based.

Is this correct that the goal of performance dominates here, so there will not be extra debug facilities, even in debug build? Any suggestions on deadlock debugging?

vNext note: Resolving this issue will require breaking binary compatibility. We won't be able to accept pull requests for this issue until the vNext branch is available. See #169 for more information.