Prevent claiming outside of the worldborder

src/main/java/me/ryanhamshire/GriefPrevention/Claim.java

@@ -26,6 +26,7 @@ import org.bukkit.Location;
 import org.bukkit.Material;
 import org.bukkit.World;
 import org.bukkit.World.Environment;
+import org.bukkit.WorldBorder;
 import org.bukkit.block.Block;
 import org.bukkit.block.BlockState;
 import org.bukkit.entity.Entity;
@@ -767,4 +768,10 @@ public class Claim
         }
         return true;
     }
+
+    public boolean isInsideBorder() {
+        WorldBorder worldBorder = this.getLesserBoundaryCorner().getWorld().getWorldBorder();
+        return worldBorder.isInside(this.lesserBoundaryCorner) && worldBorder.isInside(this.greaterBoundaryCorner);
+    }
+
 }

src/main/java/me/ryanhamshire/GriefPrevention/DataStore.java

@@ -965,6 +965,13 @@ public abstract class DataStore
             return result;
         }
 
+        if (creatingPlayer != null && newClaim.isInsideBorder()) {
+            result.succeeded = false;
+            result.claim = null;
+            creatingPlayer.sendMiniMessage("<red>You can't claim outside of the worldborder", null); // TODO MINIMESSAG + CONFIG
+            return result;
+        }
+
         //if worldguard is installed, also prevent claims from overlapping any worldguard regions
         if (GriefPrevention.instance.config_claims_respectWorldGuard && this.worldGuard != null && creatingPlayer != null)
         {