This plugin checks for shulker boxes with the same ID when a non-player inventory is opened. If it finds them, it sends a warning. It assigns IDs to shulker boxes that don't have an ID in the same event, block place event, block break event and in certain commands.

Commands:
/shulkers [<boolean>]: Searches for all placed shulker boxes, if the argument is anything but "false", it also checks insides of containers. Triggers duplicate warnings (permission:
shulkerid.shulkers)
/idshulkers [<boolean>]: Assigns IDs to all shulker boxes, if the argument is anything but "false", it overwrites all IDs it finds. (permission:
shulkerid.idshulkers)
/configreload: Reloads config.yml file (permission:
shulkerid.config)

Replaceable:
"{player}" for player name, "{count}" for shulker boxes with same id count, "{id}" for id of the repeating shulker boxes, "{time}" for unix timestamp with miliseconds.
Config:
WebhookURL: The URL for your discord webhook (used for warnings). "console" for console warnings, "none" for no warnings.
Only applicable if WebhookURL is not "none" or "console":
WebhookName: The name of your discord webhook.
WebhookAvatarUR: The URL for the avatar of your discord webhook.
WebhookTextToSpeech: Whether to use text-to-speech when sending webhook messages.
WebhookMessage: The warning that gets sent by the webhook. Supports replaceable.
Only applicable if WebhookURL is "console":
ConsoleMessage: The warning that gets sent to the console. Supports replaceable.
Command: Command that gets executed when a warning is sent. Supports replaceable.

"DoNotTouch.txt" file stores the ID that will be assigned to the next shulker box and it gets increased by 1 after it gets assigned. If you don't know what you're doing, don't touch it!