CrashPatch is a Minecraft (1.8.9) modification port of the BetterCrashes Minecraft modification (1.7.10) which is a port of the VanillaFix Minecraft modification (1.12.2).

CrashPatch essentially wraps the game in a try catch which stops the game from closing when something goes wrong (aka a crash).

When CrashPatch detects a crash, it will exit the current world and display a screen where you can either return playing the game, find solutions to the crash, or open / upload the crash log.

If Minecraft crashes while loading / initializing the game, it will not be able to recover but the ability to see possible solutions and / or open and upload crash logs will be available.