An updated version of https://www.curseforge.com/minecraft/mc-mods/screen-size for Minecraft 1.12.2.
An essential utility mod that will help you change your resolution both in fullscreen and windowed modes!
Essentials:
The default key to access the gui is the + on the number pad; this is a configurable key.
Press it and you are greeted with this gui:
The errors are actually helpful:
The Screen Resizer Team
