Occasional crash when loading a game with a placed tower

[funklord]

I try to keep towers only in my inventory because occasionally when I load a game with placed towers the game crashes and I need to deactivate the mod to remove those towers in order to work around this issue.

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Mods: Defense Tower (v. 1.2.0)

java.lang.NullPointerException: Cannot invoke "necesse.entity.mobs.Mob.isSamePlace(necesse.entity.Entity)" because "this.attacker" is null
at DefenseTower.objectEntity.DefenseTowerEntity.attackMob(DefenseTowerEntity.java:151)
at java.base/java.util.Optional.ifPresent(Unknown Source)
at DefenseTower.objectEntity.DefenseTowerEntity.serverTick(DefenseTowerEntity.java:107)
at necesse.entity.manager.EntityManager.lambda$serverTick$37(EntityManager.java:563)
at necesse.entity.manager.TileEntityList.lambda$serverTick$5(TileEntityList.java:299)
at java.base/java.util.concurrent.ConcurrentHashMap.forEach(Unknown Source)
at necesse.entity.manager.TileEntityList.serverTick(TileEntityList.java:289)
at necesse.entity.manager.EntityManager.lambda$serverTick$38(EntityManager.java:562)
at necesse.engine.gameLoop.tickManager.PerformanceTimerManager.recordPerformance(PerformanceTimerManager.java:113)
at necesse.engine.gameLoop.tickManager.Performance.record(Performance.java:10)
at necesse.entity.manager.EntityManager.serverTick(EntityManager.java:561)
at necesse.engine.gameLoop.tickManager.PerformanceTimerManager.recordPerformance(PerformanceTimerManager.java:113)
at necesse.engine.gameLoop.tickManager.Performance.record(Performance.java:10)
at necesse.level.maps.Level.serverTick(Level.java:572)
at necesse.engine.world.LevelManager.serverTick(LevelManager.java:38)
at necesse.engine.world.World.serverTick(World.java:208)
at necesse.engine.network.server.Server.tick(Server.java:302)
at necesse.engine.gameLoop.tickManager.PerformanceTimerManager.recordPerformance(PerformanceTimerManager.java:113)
at necesse.engine.gameLoop.tickManager.Performance.record(Performance.java:10)
at necesse.engine.gameLoop.ServerGameLoop.lambda$update$1(ServerGameLoop.java:42)
at necesse.engine.gameLoop.tickManager.PerformanceTimerManager.recordConstantPerformance(PerformanceTimerManager.java:121)
at necesse.engine.gameLoop.tickManager.Performance.recordConstant(Performance.java:20)
at necesse.engine.gameLoop.ServerGameLoop.update(ServerGameLoop.java:40)
at necesse.engine.gameLoop.tickManager.TickManager.tickLogic(TickManager.java:98)
at necesse.engine.gameLoop.GameLoop.runMainGameLoop(GameLoop.java:24)
at necesse.engine.server.ServerTickThread.run(ServerTickThread.java:45)
`