This is a custom fork of Harmony 2.4.2 used by the Stardew Valley community. It's bundled with SMAPI automatically. See pardeike/Harmony for documentation and usage.
This fork is identical to the official version, except that generated method names include the patching Harmony IDs to help troubleshoot error logs:
// with original Harmony
at StardewValley.Farm.resetLocalState_Patch1(Object )
// with fork
at StardewValley.Farm.resetLocalState_PatchedBy<Pathoschild.SmallBeachFarm>(Object )The SMAPI community uses the LibHarmony.Thin version, since SMAPI manages the other dependencies.
Here's a list of changes in the forked version.