What is LKG?

[voroninp]

TokenValidationParameters class has a proprty ValidateWithLKG. What is it for? I could not find what this LKG stands for.
The documentation is pretty much useless. =(

[martincostello]

My guess would be that it stands for Last Known Good.

[pinkfloydx33]

It's "Last Known Good", per the changelog of Microsoft.IdentityModel

Introduced an injection point for external metadata management and adjusted the issuer Last Known Good (LKG) to maintain the state within the issuer validator.