How to disable vsync on Minecraft [linux>Mesa]

UPDATE: Some shaderpacks don't seem to be working with this workaround. I'll post an updated version of this guide once I find a fix for this.

NOTE: As of Mesa 18.3.3, you no longer need the MESA_GL and MESA_GLSL version overrides.

Script:
#!/bin/bash

export force_glsl_extensions_warn=true
export mesa_glthread=true
export vblank_mode=0

For Mesa versions older than 18.3.3:

Script:
#!/bin/bash

export MESA_GL_VERSION_OVERRIDE=4.5COMPAT
export MESA_GLSL_VERSION_OVERRIDE=450
export force_glsl_extensions_warn=true
export allow_higher_compat_version=true
export mesa_glthread=true
export vblank_mode=0

To execute this script automatically on startx, edit .xinitrc and add the line . ./[scriptname].sh

For about a year, I've tried and failed to properly run SEUS shaders in Minecraft using Mesa 3D. Eventually, I found a CEMU script that had environment variables that allowed me to override the default version of OpenGL + GLSL, which led to me making this lazily recorded/edited tutorial on how to properly run SEUS shaders on Linux using Mesa 3D. Note that these environment variables will work for any OpenGL game/application that does not request the core profile from Mesa.