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Please describe your question or what you need help with, in the best detain you can.
I'm trying to get the NBT to work for the custom item plugin i use named Itemsadder.

Pastebin
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I've tried:

nbt-item: id: STICK slot: 33 properties: 'TranslatableDisplayName:player_menu_stone, Slot:33, Plugin:itemsadder' count: 1 triggers: world-switch, respawn enabled-worlds: Lobby, towny, towny_nether, towny_the_end

Please complete the following information:

• Resource Version and Build Number: ItemJoin-5.2.5-SNAPSHOT-b847 

• Server Version [e.g. Paper-1.19.2

Any help would be appreciated!

OK I got the custom texture to load by using model-data: but the nbt isn't working

https://paste.helpch.at/ipidocegiz.cs

Found an alternative way to do it for the moment but would be great and appreciated of you could make itemjoin compatible with Itemsadder nbt, that or if it's already possible, you can show us how. thanks

Ironically my latest update to the snapshots may have accidentally implemented a feature for adding the itemsadder information.
The latest snapshot contains the ability to add nested nbt data which is what it seems itemsadder is using.

Don't quote me on this as I am not 100% sure this will work since I don't know their exact nbt layout but given what you provided in the screenshots the nbtdata should be as follows;

properties: 'itemsadder:[id:player_menu_stone#namespace:customitems]'

You will need the latest snapshot for this to work;
Link: https://ci.craftationgaming.com/job/ItemJoin/849/
Remember to remove your old ItemJoin.jar file

sorry been unwell, i will test this later today.