When loading a pack with overlays in 1.21, the overlays will output older resource names (functions instead of function).

Notes

Likely a consequence of this code snippet:

When 1.21+ support was added, we needed a way to know how to output the correct resource naming since importing would support both the old and the new. A source map was introduced to figure out the correct naming based on the pack format. Since overlay packs don't keep track of a pack format, it defaults to the wrong one.

Recommended Changes

• Overlay packs should likely match the pack format that's listed in the overlays section of the pack.mcmeta file. This might be a range, so perhaps defaulting to the newest number in said range would be the best.
  • Inheriting the pack_format from the parent pack would likely end up with incorrect behavior as often you are writing overlays for older pack formats.