Unsure if this also applies to OP's issue, but I also am unable to use \n as an escape character in 25w04a, which has lead to a multitude of my text functions in my datapack breaking.
[media]Can confirm: I tried to make a crafting_transmute recipe in 25w02a that utilized adding Component data onto an item that already had other component data.
The item was able to add the data onto the input as expected, but the output item had to be different. Would be nice if we could keep both the input and output the same!
I didn't see that this issue already exists in MC-272643, but I'm hoping it gets fixed regardless.
I think a good fix for this would be for the command to simply grant the player all advancements available, without any toasts or audio whatsoever.
If a player wanted to be granted every advancement (like you said), it's unlikely they're intending to read all of them as they come through.
Can confirm: the same issue occurs with consuming oversized milk buckets.
I think the issue can be easily replicated by trying to consume any oversized item that would normally give you another, such as stews.
Also apparent in 25w21a… I thought this was a rendering problem with my machine. Glad I checked here first!
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