: A game update changed the original code that the mod was trying to "inject" into.
For anyone looking to dive into script modding, templates like the Sims 4 Scripting Template on GitHub include injector.py to help you get started with "prettier" and more efficient coding.
: You’ll find versions of it inside popular mods like Basemental Drugs and the XML Injector library. Why You Might See It in Error Logs
Are you looking to a specific error involving this script, or are you interested in using it for a mod you're building? XML Injector version 2 - Mod The Sims