I have recently updated from 1.17 to 1.18 and I'm finding some strange behavior now with Yaml files that have duplicate top-level keys.
I will attempt to put together a reproduction case with test data, but I believe the problem is somewhere in this method:
I am using default LoadingConfig options, so duplicate keys should be allowed.
The strange thing is that if duplicate keys exist at the top level, other (non-duplicate) keys at the top level get removed. I am missing entire sections in certain configs. Cleaning them up by removing the duplicate keys fixes the problem, but I have users that may not know to do that, and their previously-working files may break in very unexpected ways when they update.
I will do my best to come back with an example, I realize this is a vague bug report without but I was hoping to get the ball rolling.
Thank you for your time!