Entering only colons into multiplayer Direct Connection & pressing enter crashes the game

The bug

Entering any number of of only colons ":" into the Direct Connection text box, multiplayer will display a greyed out "Join Server" box. Pressing the Enter key anyway will crash the game.

The game will still _wrongly? attempt to connect if enter is pressed with the text field empty, but no crash occurs without the presence of any colons. The presence of any other character other than just colons will cause the "Join Server" button to become clickable and the crash will not occur.

This crash does not occur in the Add Server menu as pressing enter will do nothing.

Stack trace

21w03a: [^crash-2021-01-23_20.22.31-client.txt]

Description: keyPressed event handler

java.lang.ArrayIndexOutOfBoundsException: 0
	at edj.a(SourceFile:63)
	at dtk.<init>(SourceFile:41)
	at dww.a(SourceFile:233)
	at dww.f(SourceFile:177)
	at dtq.h(SourceFile:70)
	at dtq.a(SourceFile:38)
	at dpo.a(SourceFile:351)
	at duk.a(SourceFile:451)
	at dpo.a(SourceFile:349)
	at dpo.c(SourceFile:439)
	at aow.execute(SourceFile:94)
	at dpo.b(SourceFile:439)
	at org.lwjgl.glfw.GLFWKeyCallbackI.callback(GLFWKeyCallbackI.java:37)
	at org.lwjgl.system.JNI.invokeV(Native Method)
	at org.lwjgl.glfw.GLFW.glfwWaitEventsTimeout(GLFW.java:3174)
	at com.mojang.blaze3d.systems.RenderSystem.limitDisplayFPS(SourceFile:140)
	at dpq.e(SourceFile:1076)
	at dpq.e(SourceFile:688)
	at net.minecraft.client.main.Main.main(SourceFile:215)