Hey Bruhhmangod,
I'm sorry to hear that happened, but this feature does actually already exist in Wurst. If you pause the game and open the "Statistics" screen, you'll find a hidden "Disable Wurst" button. Pressing it completely hides Wurst from your screen, disables chat commands like .help, etc.
By default, this feature leaves an "Enable Wurst" button visible in the Statistics screen, so that you can easily turn Wurst back on. If your friend is likely to check the Statistics screen, there is an option to remove that button too (Navigator > Disable Wurst > Hide enable button). However, this option will leave you unable to use Wurst until you fully restart the game, so whether or not you want to use it is a trade-off between convenience and stealth.
Hope this helps you avoid similar situations in the future!
