Crash when doing: CTRL+SHIFT to mass remove code in command block

The crash happens every time by doing this:

1) CTRL+C on a command block (any style) to get an NBT command block (with copied text inside)

2)  Place down NBT command block & attempt to do: CTRL+SHIFT to mass remove 

code from it, or remove a few lines.. either way... the result is the same.

3) INSTANT CRASH.

However, IF you COPY/PASTE coding INTO the command block (I.E. /summon ~ ~1 ~ zombie[NBT DATA]{javascript} replace , The code will work fine. and if you go to CTRL+SHIFT to copy the code from THAT command block.. again it works fine. 

The crash ONLY happens if you CTRL+C to get the saved NBTdata command block... place that down.. adn then try to CTRL+SHIFT to copy information from the NBT command block.

1.14.2\: [^crash-2019-06-12_16.58.33-client.txt]

Description: Rendering screen

java.lang.StringIndexOutOfBoundsException: String index out of range: -814
	at java.lang.String.substring(String.java:1919)
	at cww.renderButton(SourceFile:413)
	at cwo.render(SourceFile:83)
	at dam.render(SourceFile:290)
	at dkk.a(SourceFile:686)
	at cvk.e(SourceFile:954)
	at cvk.b(SourceFile:411)
	at net.minecraft.client.main.Main.main(SourceFile:154)


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

-- Head --
Thread: Client thread
Stacktrace:
	at java.lang.String.substring(String.java:1919)
	at cww.renderButton(SourceFile:413)
	at cwo.render(SourceFile:83)
	at dam.render(SourceFile:290)

-- Screen render details --
Details:
	Screen name: daw
	Mouse location: Scaled: (240, 135). Absolute: (960.000000, 540.000000)
	Screen size: Scaled: (480, 270). Absolute: (1920, 1080). Scale factor of 4.000000

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [djx['hooptiecoupe'/2, l='MpServer', x=187.77, y=9.00, z=241.55]]
	Chunk stats: MultiplayerChunkCache: 729, 504
	Level seed: 0
	Level generator: ID 01 - flat, ver 0. Features enabled: false
	Level generator options: {}
	Level spawn location: World: (170,2,215), Chunk: (at 10,0,7 in 10,13; contains blocks 160,0,208 to 175,255,223), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 490061 game time, 6000 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at dhn.a(SourceFile:421)
	at cvk.b(SourceFile:1923)
	at cvk.b(SourceFile:426)
	at net.minecraft.client.main.Main.main(SourceFile:154)

-- System Details --
Details:
	Minecraft Version: 1.14.2
	Operating System: Windows 10 (amd64) version 10.0
	Java Version: 1.8.0_51, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 790782936 bytes (754 MB) / 2080374784 bytes (1984 MB) up to 2147483648 bytes (2048 MB)
	JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
	Launched Version: 1.14.2
	LWJGL: 3.2.1 build 12
	OpenGL: GeForce GTX 1050/PCIe/SSE2 GL version 4.6.0 NVIDIA 399.01, NVIDIA Corporation
	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: vanilla, file/1.13.2 vanilla.zip
	Current Language: English (US)
	CPU: 8x Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz