Multiplayer section

When entering the multiplayer server you can make your game crashes and says ticking screen error
Here's the crash log:

---- Minecraft Crash Report ----
// Why is it breaking :(

Time: 4/5/17 8:34 PM
Description: Ticking screen

java.lang.NullPointerException: Ticking screen
	at io.netty.bootstrap.Bootstrap.checkAddress(Bootstrap.java:358)
	at io.netty.bootstrap.Bootstrap.doResolveAndConnect(Bootstrap.java:180)
	at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:162)
	at io.netty.bootstrap.Bootstrap.connect(Bootstrap.java:143)
	at bqv.b(SourceFile:241)
	at bqv.a(SourceFile:45)
	at bqv$1.a(SourceFile:144)
	at gd.l(SourceFile:381)
	at bqv.a(SourceFile:254)
	at blp.e(SourceFile:115)
	at bgr.t(SourceFile:1585)
	at bgr.av(SourceFile:956)
	at bgr.a(SourceFile:396)
	at net.minecraft.client.main.Main.main(SourceFile:123)