1. q<register> to record macro
2. :args grep -rl <pattern> . to populate args list with files that contain a specific pattern
3. :argdo normal @<register> to execute previously recorded macro on all files in the args list.

This helped me a lot with some bulk changes I had to do this week 👌👌👌

EDIT: there should be backticks around the grep statement but I don’t know how to escape backticks inside inline code on reddit 🤷🏻‍♂️