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Hacks, and color mod v1 by Vaakir with the colod mod v2 from nitrogem35
< Feedback on Gats.io - Vaakir's hack pack GUI
You'll need to have a userscript manager installed first, such as tampermonkey or violentmonkey. Then, come back here, and install the script. When you next load gats.io, the menu should open automatically.
However, it sounds like you're on a school-issued chromebook. Most schools block extensions, so there's a good chance you won't be able to use this script.
how do you use the scripted? what button is it, im on a chromebook