[MC-226192] Crash upon attempting to create a new scoreboard objective: java.lang.NullPointerException: Cannot invoke "String.toLowerCase(java.util.Locale)" because "â˜ƒ" is null

The bug

I ran this command and crashed out to the launcher (from this page):

/scoreboard objectives add clicked minecraft.used:minecraft.carrot_on_a_stick

After loading the world back up I was unable to recreate the issue.

Stack trace

21w20a: crash-2021-05-23_16.12.41-client.txt

Description: keyPressed event handler

java.lang.NullPointerException: Cannot invoke "String.toLowerCase(java.util.Locale)" because "â˜ƒ" is null
	at di.b(SourceFile:190)
	at dz.listSuggestions(SourceFile:61)
	at com.mojang.brigadier.tree.ArgumentCommandNode.listSuggestions(ArgumentCommandNode.java:69)
	at com.mojang.brigadier.CommandDispatcher.getCompletionSuggestions(CommandDispatcher.java:598)
	at dwm.a(SourceFile:184)
	at dyw.b(SourceFile:77)
	at dwr.d(SourceFile:152)
	at dwr.b(SourceFile:147)
	at dwr.a(SourceFile:290)
	at dxg.a(SourceFile:64)
	at dzz.a(SourceFile:123)
	at dyw.a(SourceFile:87)
	at duw.a(SourceFile:367)
	at dzz.a(SourceFile:489)
	at duw.a(SourceFile:363)
	at duw.c(SourceFile:455)
	at aqe.execute(SourceFile:102)
	at duw.b(SourceFile:455)
	at org.lwjgl.glfw.GLFWKeyCallbackI.callback(GLFWKeyCallbackI.java:37)
	at org.lwjgl.system.JNI.invokeV(Native Method)
	at org.lwjgl.glfw.GLFW.glfwPollEvents(GLFW.java:3101)
	at com.mojang.blaze3d.systems.RenderSystem.flipFrame(SourceFile:165)
	at dpa.e(SourceFile:310)
	at duy.f(SourceFile:1130)
	at duy.e(SourceFile:721)
	at net.minecraft.client.main.Main.main(SourceFile:217)