The `piglin_barter.json` file inside 20w09a has a stray "functions" of "set_count uniform 1-5" in the first pool.
According to slicedlime's snapshot video (https://youtu.be/yJHRnaPSRbY?t=185), fire charges are supposed to have 1-5 items, but the respective entry in piglin_barter.json is missing a "functions" key. It looks like this stray "functions" key is supposed to be there.
The effects of this misplacement are:
Because the "functions" key is missing, we will only able to receive one fire charge from one bartering;
The stray "functions" inside pool applied to the item stack generated, so the designated number of items will be overwritten by this. This can be seen on Xisuma's snapshot video (https://youtu.be/DAb7s-ir9OM?t=561) where he get one leather and one quartz (from different barters), but these items are supposed to be more than one. This effect will probably overwrite the previous point so this mistake is probably not visible from fire charge alone.
Thank you for your report!
However, this issue is a Duplicate of MC-173165.
That ticket has already been resolved as Fixed. The fix will arrive in the next version or is already included in the latest development version of the game, you can check the Fix Version/s field in that ticket to learn more.
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