When getting an item display name from the item meta, if the item display name contains the color black, it will be returned without the color. Example code:

@EventHandler
public void onInventoryClick(InventoryClickEvent event) {
Player player = (Player) event.getWhoClicked();
ItemStack item = event.getCurrentItem();
player.sendMessage(item.getItemMeta().getDisplayName());
}

I have given image examples below run with the same code.

When clicking the item in "black item.png", it outputs "black output.png"

When clicking the item in "green item.png", it outputs "green output.png"