[MC-234733] Closing game during world loading screen causes errors

The bug

When closing the game while loading a world, an error (java.util.concurrent.RejectedExecutionException: null) occurs. This is similar to MC-187583. The exception message thrown is "Cound not schedule mailbox" (sic). A crash has occurred once, but a crash report was not produced.

Example 1.17.1 log (abridged)

[13:49:54] [Render thread/INFO]: Preparing spawn area: 0%
[13:49:55] [Render thread/INFO]: Preparing spawn area: 0%
[13:49:55] [Render thread/INFO]: Preparing spawn area: 1%
(...)
[13:50:09] [Render thread/INFO]: Preparing spawn area: 89%
[13:50:09] [Render thread/INFO]: Time elapsed: 15197 ms
[13:50:10] [Render thread/INFO]: Stopping!
[13:50:10] [Server thread/ERROR]: Cound not schedule mailbox
java.util.concurrent.RejectedExecutionException: null
	at java.util.concurrent.ForkJoinPool.externalPush(ForkJoinPool.java:1889) ~[?:?]
	at java.util.concurrent.ForkJoinPool.externalSubmit(ForkJoinPool.java:1930) ~[?:?]
	at java.util.concurrent.ForkJoinPool.execute(ForkJoinPool.java:2462) ~[?:?]
	at aqy.h(SourceFile:135) ~[1.17.1.jar:?]
	at aqy.a(SourceFile:124) ~[1.17.1.jar:?]
	at abg.a(SourceFile:125) ~[1.17.1.jar:?]
	at abg.a(SourceFile:91) ~[1.17.1.jar:?]
	at aqx$1.a(SourceFile:44) ~[1.17.1.jar:?]
	at abu.a(SourceFile:104) ~[1.17.1.jar:?]
	at abu.a(SourceFile:100) ~[1.17.1.jar:?]
	at abu.a(SourceFile:61) ~[1.17.1.jar:?]
	at bwq.a(SourceFile:220) ~[1.17.1.jar:?]
	at bwq.a(SourceFile:196) ~[1.17.1.jar:?]
	at deq.a(SourceFile:261) ~[1.17.1.jar:?]
	at deq.a(SourceFile:160) ~[1.17.1.jar:?]
	at deq.a(SourceFile:140) ~[1.17.1.jar:?]
	at deq.a(SourceFile:458) ~[1.17.1.jar:?]
	at des.a(SourceFile:76) ~[1.17.1.jar:?]
	at abr.a(SourceFile:637) ~[1.17.1.jar:?]
	at bxf.b(SourceFile:81) ~[1.17.1.jar:?]
	at abr.a(SourceFile:365) ~[1.17.1.jar:?]
	at net.minecraft.server.MinecraftServer.b(SourceFile:891) ~[1.17.1.jar:?]
	at net.minecraft.server.MinecraftServer.a(SourceFile:831) ~[1.17.1.jar:?]
	at faq.a(SourceFile:96) ~[1.17.1.jar:?]
	at net.minecraft.server.MinecraftServer.x(SourceFile:697) ~[1.17.1.jar:?]
	at net.minecraft.server.MinecraftServer.a(SourceFile:270) ~[1.17.1.jar:?]
	at java.lang.Thread.run(Thread.java:831) [?:?]

Example 24w10a log (abridged)

(...)
[19:01:13] [Render thread/INFO]: Preparing spawn area: 0%
[19:01:13] [Render thread/INFO]: Preparing spawn area: 0%
[19:01:13] [Render thread/INFO]: Preparing spawn area: 0%
[19:01:14] [Server thread/INFO]: Changing view distance to 9, from 10
[19:01:14] [Server thread/INFO]: Changing simulation distance to 5, from 0
[19:01:14] [Render thread/INFO]: Time elapsed: 1347 ms
[19:01:14] [Render thread/INFO]: Stopping!
[19:01:14] [IO-Worker-13/ERROR]: Cound not schedule mailbox
java.util.concurrent.RejectedExecutionException: Task IOWorker-chunk 2 false rejected from java.util.concurrent.ThreadPoolExecutor@4944508b[Shutting down, pool size = 1, active threads = 1, queued tasks = 0, completed tasks = 15302]
	at java.base/java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2065) ~[?:?]
	at java.base/java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:833) ~[?:?]
	at java.base/java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1365) ~[?:?]
	at bmy.i(SourceFile:135) [24w10a.jar:?]
	at bmy.run(SourceFile:105) [24w10a.jar:?]
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136) [?:?]
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) [?:?]
	at java.base/java.lang.Thread.run(Thread.java:833) [?:?]
[19:01:14] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 1037193137ms or 20743862 ticks behind

How to reproduce

1. Start the game and load a world.
2. While the world loading screen is shown, close the window by pressing the X button.
3. Look at the log.

Note: The game window might not close immediately after the X button of the window has been pressed, but it closes as soon as loading has (nearly) finished.
Look at the log file after the window has closed.