The bug
Due to MC-150020 the composter is now under "Decoration" instead of "Miscellaneous" in the Creative inventory. Apparently the recipe advancement was moved respectively as well:
1.15.2:
minecraft:recipes/misc/composter
20w06a:
minecraft:recipes/decorations/composter
However, it appears there is no datafixer for this, causing the following warning message when upgrading old worlds and causing the player to lose the advancement.
Ignored advancement 'minecraft:recipes/misc/composter' in progress file ###.json - it doesn't exist anymore?
Comments


I can't reproduce this upgrading either a 1.14 or 1.15 world to latest - I don't get a message and the recipe is already unlocked still.

@unknown I can still reproduce with 1.16-pre2.
Create world in 1.15.2 and execute:
/advancement grant @s only recipes/misc/composter
Upgrade to pre-release and run
/advancement revoke @s only minecraft:recipes/decorations/composter
❌ Couldn't revoke advancement [...] as they don't have it
Please note that this might be Won't fix, because it only removes the advancement triggering the recipe unlock, the recipe itself persists.
From the log:
Ignored advancement 'minecraft:recipes/misc/composter' in progress file G:\Minecraft\Snapshot\saves\Data Fixer Composter\advancements\f5e14d7c-b630-40f7-8582-4e0e2bd87435.json - it doesn't exist anymore?

The following 1.15 advancement gets removed from advancements/f5e14d7c-b630-40f7-8582-4e0e2bd87435.json
:
{
"minecraft:recipes/misc/composter": {
"criteria": {
"has_wood_slab": "2020-05-28 22:56:19 +0200",
"has_the_recipe": "2020-05-28 22:56:19 +0200"
},
"done": true
},
"DataVersion": 2230
}
This is what it should be upgraded to in 1.16:
"minecraft:recipes/decorations/composter": {
"criteria": {
"has_wood_slab": "2020-06-09 15:42:52 +0200"
},
"done": true
},
,
"DataVersion": 2557
}

Really odd - I see why I'd get such a log message because there is in fact no data fixer for this, but...I'm not getting the log message. I do, however, get the "Couldn't revoke advancement" message, though the recipe exists. I am curious why I'm not getting the log message...
I'd regard upgrading issues as serious no matter how small, hope this gets fixed before release.