The bug
Craft a trimmed armor at a Smithing Table
This sentence has a grammar problem. The word "armor" is uncountable, just like the word "water". There is no "a", "one" or "two" waters. And similarly, no "an armor" either.
Instead, it should be either "trimmed armor" without the "a", or "a trimmed armor piece". And considering this is about one single piece of the full set specifically, the latter is the correct one.
To reproduce
/tellraw @p {"translate": "advancements.adventure.trim_with_any_armor_pattern.description"}
Comments 4
@@unknown Yes agreed, but then with that phrasing I would suggest "Trim a piece of armor using a Smithing Table" instead.
also applies to "Repair a damaged Wolf Armor using Armadillo Scutes" (advancements.husbandry.repair_wolf_armor.description) https://crowdin.com/editor/minecraft/10038/enus-enca?view=comfortable#5366252 note also that this string is misleading, as you actually have to fully repair the armor.
This and the existing ticket affect 1.20.5-pre1
can confirm