java.lang.NullPointerException: Updating screen events

Minecraft crashes when trying to join a REALMS server about half the time, also occurs when loading non-REALMS games.

---- Minecraft Crash Report ----
// Oh - I know what I did wrong!

Time: 7/8/17 8:52 PM
Description: Updating screen events

java.lang.NullPointerException: Updating screen events
	at bli.k(SourceFile:386)
	at bkg.k(SourceFile:217)
	at bli.q(SourceFile:374)
	at bhz.t(SourceFile:1625)
	at bhz.az(SourceFile:1000)
	at bhz.a(SourceFile:419)
	at net.minecraft.client.main.Main.main(SourceFile:123)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Thread: Client thread
Stacktrace:
	at bli.k(SourceFile:386)
	at bkg.k(SourceFile:217)
	at bli.q(SourceFile:374)

-- Affected screen --
Details:
	Screen name: bkg
Stacktrace:
	at bhz.t(SourceFile:1625)
	at bhz.az(SourceFile:1000)
	at bhz.a(SourceFile:419)
	at net.minecraft.client.main.Main.main(SourceFile:123)

-- System Details --
Details:
	Minecraft Version: 1.12
	Operating System: Windows 7 (amd64) version 6.1
	Java Version: 1.8.0_25, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 62515960 bytes (59 MB) / 237948928 bytes (226 MB) up to 3207856128 bytes (3059 MB)
	JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx3G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Launched Version: 1.12
	LWJGL: 2.9.4
	OpenGL: AMD Radeon HD 7700M Series GL version 4.5.13474 Compatibility Profile Context 0, ATI Technologies Inc.
	GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

	Using VBOs: Yes
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: 
	Current Language: English (US)
	Profiler Position: N/A (disabled)
	CPU: 8x Intel(R) Core(TM) i7-3632QM CPU @ 2.20GHz

MCX-3553048