I have added an example of this issue happening without the /tick
command. The same reproduction steps from my first comment also apply to wither roses, campfires, cacti, fires, lava. Does not apply to a magma block in the floor. If you want to reproduce the bug using magma blocks, you will have to place the magma block sticking out (just like berries, campfires, etc.) and cover the rest of the floor in slabs. I have added a video for that too.
Here’s a simple way to reproduce the issue in the latest snapshot. play on a flat world with minimum simulation distance for quickest results.
Steps to reproduce:
Build a 5x5 containment chamber with a berry bush in the middle, as shown in the video
spawn a villager inside
run the command /tick spring 1d
[media]this bug appears to be fixed in 25w32a
The reason this bug occurs is because the components of the room containing the copper bulbs do not have the trial chamber copper bulb degradation processor.
[media]In both cases, the wolf has a weight of 2, but it’s relative rarity is different. in 1.21.4, the total weight of all mobs was 8, meaning the wolf had a 2/8 chance to spawn, now the total weight is 48, meaning that the wolf has a 2/48 chance to spawn, indirectly making the wolf much more rare. you can see in the second .json file that farm animals have been added to the list of possible spawns, which is what increases the total weight from 8 to 48
The game rule seems to only take effect after reloading the world