Minecraft Forums

it says "it looks like you are using an unsupported modified version of the game"

Here is the full crash report.

Ok here it is

---- Minecraft Crash Report ----

WARNING: coremods are present:
Inventory Tweaks Coremod (InventoryTweaks-1.63.jar)
EnderCorePlugin (EnderCore-1.12.2-0.5.43.jar)
CorePlugin (SmoothFont-mc1.12.2-1.16.1.jar)
BedPatch (bedpatch-2.2-1.12.2.jar)
ForgelinPlugin (Forgelin-1.8.0.jar)
IELoadingPlugin (ImmersiveEngineering-core-0.12-86.jar)
LoadingPlugin (ResourceLoader-MC1.12.1-1.5.3.jar)
SplashAnimationCoremod (SplashAnimation-0.2.0.jar)
Do not report to Forge! (If you haven't disabled the FoamFix coremod, try disabling it in the config! Note that this bit of text will still appear.) (foamfix-0.10.2-1.12.2.jar)
OpenModsCorePlugin (OpenModsLib-1.12.2-0.12.1.jar)
CTMCorePlugin (CTM-MC1.12.2-0.3.2.20.jar)
Contact their authors BEFORE contacting forge

// Sorry

Time: 12/25/18 12:14 PM
Description: Initializing game

org.lwjgl.LWJGLException: Pixel format not accelerated
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)
at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)
at org.lwjgl.opengl.Display.createWindow(Display.java:306)
at org.lwjgl.opengl.Display.create(Display.java:848)
at org.lwjgl.opengl.Display.create(Display.java:757)
at org.lwjgl.opengl.Display.create(Display.java:739)
at net.minecraft.client.Minecraft.func_175609_am(Minecraft.java:644)
at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:457)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:377)
at net.minecraft.client.main.Main.main(SourceFile:123)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

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

-- Head --
Thread: Client thread
Stacktrace:
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)
at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)
at org.lwjgl.opengl.Display.createWindow(Display.java:306)
at org.lwjgl.opengl.Display.create(Display.java:848)
at org.lwjgl.opengl.Display.create(Display.java:757)
at org.lwjgl.opengl.Display.create(Display.java:739)
at net.minecraft.client.Minecraft.func_175609_am(Minecraft.java:644)
at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:457)

-- Initialization --
Details:
Stacktrace:
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:377)
at net.minecraft.client.main.Main.main(SourceFile:123)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

-- System Details --
Details:
Minecraft Version: 1.12.2
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.8.0_51, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 220142360 bytes (209 MB) / 739246080 bytes (705 MB) up to 4056416256 bytes (3868 MB)
JVM Flags: 4 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx4352m -Xms256m -XX:PermSize=256m
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
FML:
Loaded coremods (and transformers):
Inventory Tweaks Coremod (InventoryTweaks-1.63.jar)
invtweaks.forge.asm.ContainerTransformer
EnderCorePlugin (EnderCore-1.12.2-0.5.43.jar)
com.enderio.core.common.transform.EnderCoreTransformer
com.enderio.core.common.transform.SimpleMixinPatcher
CorePlugin (SmoothFont-mc1.12.2-1.16.1.jar)
bre.smoothfont.asm.Transformer
BedPatch (bedpatch-2.2-1.12.2.jar)
com.mordenkainen.bedpatch.BedPatchASM
ForgelinPlugin (Forgelin-1.8.0.jar)

IELoadingPlugin (ImmersiveEngineering-core-0.12-86.jar)
blusunrize.immersiveengineering.common.asm.IEClassTransformer
LoadingPlugin (ResourceLoader-MC1.12.1-1.5.3.jar)
lumien.resourceloader.asm.ClassTransformer
SplashAnimationCoremod (SplashAnimation-0.2.0.jar)
pl.asie.splashanimation.core.SplashProgressTransformer
Do not report to Forge! (If you haven't disabled the FoamFix coremod, try disabling it in the config! Note that this bit of text will still appear.) (foamfix-0.10.2-1.12.2.jar)
pl.asie.foamfix.coremod.FoamFixTransformer
OpenModsCorePlugin (OpenModsLib-1.12.2-0.12.1.jar)
openmods.core.OpenModsClassTransformer
CTMCorePlugin (CTM-MC1.12.2-0.3.2.20.jar)
team.chisel.ctm.client.asm.CTMTransformer
Launched Version: forge-14.23.5.2770
LWJGL: 2.9.4
OpenGL: ~~ERROR~~ RuntimeException: No OpenGL context found in the current thread.
GL Caps:
Using VBOs: Yes
Is Modded: Definitely; Client brand changed to 'fml,forge'
Type: Client (map_client.txt)
Resource Packs:
Current Language: ~~ERROR~~ NullPointerException: null
Profiler Position: N/A (disabled)
CPU: <unknown>

I've searched for this error: "OpenGL: ~~ERROR~~ RuntimeException: No OpenGL context found in the current thread" and I found an FTB thread in which the solution was to downgrade Java.

https://forum.feed-the-beast.com/threads/opengl-error-runtimeexception-no-opengl-context-found-in-the-current-thread.132180/

[edit] The solution was for 1.7.10, I don't know if that would still help.

This is THE most common crash and is always caused by broken drivers, follow the instructions here http://hopper.minecraft.net/help/pixel-format-not-accelerated/support/