Currently on Dev #388 / CS-Core Lib #790 / Spigot 1.15.1

Periodically getting the following:

04.01 13:03:59 [Server] Craft Scheduler Thread - 52/WARN Plugin Slimefun vDEV - 388 (git 9f61896f) generated an exception while executing task 41
04.01 13:03:59 [Server] INFO java.lang.NullPointerException: null
04.01 13:03:59 [Server] INFO at me.mrCookieSlime.Slimefun.api.inventory.BlockMenu.serializeLocation(BlockMenu.java:17) ~[?:?]
04.01 13:03:59 [Server] INFO at me.mrCookieSlime.Slimefun.api.inventory.BlockMenu.save(BlockMenu.java:53) ~[?:?]
04.01 13:03:59 [Server] INFO at me.mrCookieSlime.Slimefun.api.BlockStorage.save(BlockStorage.java:270) ~[?:?]
04.01 13:03:59 [Server] INFO at me.mrCookieSlime.Slimefun.api.BlockStorage.save(BlockStorage.java:234) ~[?:?]
04.01 13:03:59 [Server] INFO at io.github.thebusybiscuit.slimefun4.core.services.AutoSavingService.saveAllBlocks(AutoSavingService.java:66) ~[?:?]
04.01 13:03:59 [Server] INFO at org.bukkit.craftbukkit.v1_15_R1.scheduler.CraftTask.run(CraftTask.java:81) ~[spigot-1.15.1.jar:git-Spigot-492a779-e7202cd]
04.01 13:03:59 [Server] INFO at org.bukkit.craftbukkit.v1_15_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:54) [spigot-1.15.1.jar:git-Spigot-492a779-e7202cd]
04.01 13:03:59 [Server] INFO at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_211]
04.01 13:03:59 [Server] INFO at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_211]
04.01 13:03:59 [Server] INFO at java.lang.Thread.run(Thread.java:748) [?:1.8.0_211]

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