I have a suggestion on HOW TO STOP GRIEFERS!

There can be a list of griefers on the side of the [Players List] menu.

If someone grieves your world; you can report that player to grieving. If that player has been reported more than 3-5 times for grieving; they will be added to (The griefers list) the side of the [Players List]. When a griefer tries to join a server, the owner of the server will get a warning (like a report abuse box warning) that says: WARNING : A griefer: [Player's Name] is joining your world. Do you want to allow this player to join?

You will have the option to ban this player from your world which you will have a [YES] or [NO] button on the bottom,

If the owner is not Online; the griefer will get a notification saying the owner is not online. The griefer will not be able to join the server until the owner accepts the player. If the owner rejects the player, the griefer will get a notification saying he wasn't invited to the server. If it is a Read Only world, the server will be the same like it is now.

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