Advancement titles that are longer than roughly 30 characters don't render the later characters in the advancement menu, but do render them in the chat announcement and toast.
It was expected there'd be a much higher limit, like with the description, or none at all.
To reproduce (custom advancement):
Simply create an advancement with a title or change an advancent's title to be 40 characters.
Alternatively, download and enable the attached data pack.
Press
L
to observer missing characters in the menu.
To reproduce (vanilla advancement, dutch):
Set the game language to Nederlands (Nederland).
Observe the advancement "The City at the End of the Game"'s name in the menu.
Get the advancement (or revoke it) and observe the title in the chat/toast.
To reproduce (vanilla advancement, malaysian):
Set the game language to Bahasa Melayu (Malaysia).
Observe the advancement "Glow and Behold"'s name in the menu.
Get the advancement (or revoke it) and observe the title in the chat/toast.
Screenshot note: yes, it may be dutch, but that's irrelevant to the report.
Linked issues
is duplicated by 3
relates to 2
Attachments
Comments


Also happens with the dutch translation of the achievement "the city at the end of the game". see MC-209612 for further information.

Also happens with Malay translations of the "Glow and Behold", "The Healing Power of Friendship!" and the "Is It a Bird?" advancements...
For more info see MC-226968

I just discovered this bug on my own, only to find out a few other people have already discovered it lol.
Also, the advancement "The Healing Power of Friendship!
" has this issue even when using English (US). In the toast and in chat, it says it with the exclamation mark at the end, but in the advancement menu it is without the exclamation mark.
I also discovered that it's not the amount of characters that limit it, instead it is the length in pixels.
When using GUI Scale: 1, the text "The Healing Power of Friendship
" is 161px long (note that it is without the exclamation mark). The exclamation mark adds 2px, which would make it 163px long, which is apparently too long for the Advancement Menu.
However, if you use a resource pack to change the name of the advancement, you can actually get it to show text up to 162px long. For example, the letter 'p' is 6px long, but the letters 'k' and 'f' are each 5px long. So, if we replace the 'p' in "Friendship!
" with either a 'k' or an 'f', we will be reducing the length of the advancement's name by just 1px, which is just enough to show the whole text in the Advancements Menu, including the exclamation mark.
To test this yourself, you can simply create a resource pack, and in RP/assets/minecraft/lang, create a text file named en_us.json, open it and copy paste in the following text:
{
"advancements.husbandry.kill_axolotl_target.title": "The Healing Power of Friendshik!"
}
Then, reload the resource pack by using F3+T and give yourself the advancement with the following command:
/advancement grant @s only minecraft:husbandry/kill_axolotl_target
Finally, open the Advancement Menu by pressing L on your keyboard, and go in the Husbandry tab where the advancement is. It is nearly impossible to tell by just looking, but you can take a screenshot and use an image editing software to zoom in more, and you'll see that compared to how long it is without the resource pack, it is 1px longer (counting the shadow of the text too, of course).
@unknown Thanks for attaching an example pack.