As of 25w31a (1.21.9 Snapshot) pack.mcmeta handles supported versions differently to allow minor Pack Format versions. Any Packs that include a value below 65 for Resource Packs or 82 for Data Packs still requires the original fields for compatibility.
Packs with an outdated version simply state “Made for an older version of Minecraft” while any packs with a Pack Format of 14 or less instead states “Broken or incompatible”
To reproduce the issue create a resourcepack for the latest snapshot (1.21.9-rc1) and set up this pack.mcmeta file
{
"pack": {
"pack_format": 5,
"supported_formats": [5, 69],
"min_format": 5,
"max_format": 69.0,
"description": "Flightning99's Bug!"
}
}
The expected result would be a valid Resource Pack between versions 1.15 and 1.16.1 as well as between versions 1.20.2 and 1.21.9-rc1 (Latest Snapshot)
The actual result is a Resource Pack that is valid between versions 1.15 and 1.16.1 as well as between versions 1.20.2 and 1.21.8, but not any 1.21.9 development version
While this is only visual and does not limit the features of a Resource Pack, it does sting to see your custom packs labeled as “broken” simply because you wish to ensure compatibility with older versions.
Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
Please note, that mechanics of the game may change between updates.
Things such as graphics, sounds, world creation, biomes, redstone, villagers, and animals may not work the same in current versions.
Full Version History – Snapshot Version History – The official Minecraft feedback site
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