[MC-220067] Chunk corruption with command block full of certain Unicode characters

The bug

When a command block is full of characters that take more than 1 byte to store, the chunk that command block is in gets corrupted.

How to reproduce

Place a command block down.
Copy and paste this symbol "■" into the command block until the command block is full.
Save and quit to title.
Get back in the world.
→ The chunk the command block was in is re-generated; resetting everything in it

Note

■ is not the only character this works with.

Game output error message

Failed to store chunk [7, 1]
java.io.UTFDataFormatException: encoded string (■■■■■■■■...■■■■■■■■) too long: 97500 bytes
	at java.base/java.io.DataOutputStream.writeUTF(DataOutputStream.java:368)
	at java.base/java.io.DataOutputStream.writeUTF(DataOutputStream.java:332)
	at nq.a(SourceFile:65)
	at na.a(SourceFile:415)
	at na.a(SourceFile:104)
	at ng.a(SourceFile:81)
	at na.a(SourceFile:415)
	at na.a(SourceFile:104)
	at na.a(SourceFile:415)
	at na.a(SourceFile:104)
	at nk.a(SourceFile:95)
	at nk.a(SourceFile:83)
	at cnq.a(SourceFile:70)
	at cnm.a(SourceFile:153)
	at cnm.a(SourceFile:143)
	at ara$b.run(SourceFile:61)
	at aqy.g(SourceFile:91)
	at aqy.a(SourceFile:146)
	at aqy.run(SourceFile:102)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630)
	at java.base/java.lang.Thread.run(Thread.java:831)

Video

https://youtu.be/C4t2avl0Dhw
(Video by Phoenix SC)