Issue with setting displaynames of items

[Thorinwasher]

Issue

I'm having problems with setting the displayname of the items. I want one of the displaynames to be "Cancel" in red, and another be "Accept" in green.

Behavior

When triggering the GUI, these items appear to have the default names. (Barrier and Green wool)

Versions

Server:

This server is running Paper version git-Paper-426 (MC: 1.20.4) (Implementing API version 1.20.4-R0.1-SNAPSHOT) (Git: 7ccefdc) You are 9 version(s) behind Download the new version at: https://papermc.io/downloads/paper

AnvilGUI version 1.9.2-SNAPSHOT

Reproducible example

        AnvilGUI.Builder builder = new AnvilGUI.Builder();
        ItemStack itemLeft = new ItemStack(Material.BARRIER);
        ItemMeta itemMetaLeft = itemLeft.getItemMeta();
        itemMetaLeft.displayName(Component.text("Cancel").color(NamedTextColor.RED));
        itemLeft.setItemMeta(itemMetaLeft);
        ItemStack itemOutput = new ItemStack(Material.GREEN_WOOL);
        ItemMeta itemMetaOutput = itemOutput.getItemMeta();
        itemMetaOutput.displayName(Component.text("Accept").color(NamedTextColor.GREEN));
        itemOutput.setItemMeta(itemMetaOutput);
        builder.itemLeft(itemLeft).itemOutput(itemOutput).title("Type flag arguments").plugin(plugin).text("");
        builder.onClickAsync((slot, stateSnapshot) -> CompletableFuture.supplyAsync(() -> {
            if (slot == AnvilGUI.Slot.INPUT_RIGHT) {
                return Collections.emptyList();
            }
            if (slot == AnvilGUI.Slot.OUTPUT) {
                action.accept(stateSnapshot.getText()); // Do whatever action I want with the string I fetched from the anvil
            }
            return List.of(AnvilGUI.ResponseAction.close());
        }));
        builder.interactableSlots(AnvilGUI.Slot.INPUT_LEFT, AnvilGUI.Slot.INPUT_RIGHT, AnvilGUI.Slot.OUTPUT);
        builder.open(activator);

[BoBkiNN]

Same issue on 1.19.4 1.9.2-SNAPSHOT