Attempting to make over 100 worlds crashes the game.

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oh ok.
Here is the crash report:

Minecraft Crash Report ----
// You should try our sister game, Minceraft!

Time: 10/19/17 4:14 PM
Description: Updating screen events

java.lang.RuntimeException: Failed to check session lock, aborting
at bfb.i(SourceFile:64)
at bfb.<init>(SourceFile:50)
at bey.<init>(SourceFile:21)
at bez.a(SourceFile:84)
at bib.a(SourceFile:2159)
at boi.a(SourceFile:212)
at blk.a(SourceFile:337)
at boi.a(SourceFile:352)
at blk.k(SourceFile:400)
at blk.q(SourceFile:377)
at bib.t(SourceFile:1625)
at bib.az(SourceFile:1000)
at bib.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 bfb.i(SourceFile:64)
at bfb.<init>(SourceFile:50)
at bey.<init>(SourceFile:21)
at bez.a(SourceFile:84)
at bib.a(SourceFile:2159)
at boi.a(SourceFile:212)
at blk.a(SourceFile:337)
at boi.a(SourceFile:352)
at blk.k(SourceFile:400)
at blk.q(SourceFile:377)

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

– System Details –
Details:
Minecraft Version: 1.12.2
Operating System: Windows 8.1 (amd64) version 6.3
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 219528824 bytes (209 MB) / 368996352 bytes (351 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
Launched Version: 1.12.2
LWJGL: 2.9.4
OpenGL: AMD Radeon HD 7600G GL version 4.2.12422 Compatibility Profile Context 13.152.1.3000, 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: 4x AMD A8-4555M APU with Radeon(tm) HD Graphics