VS code to treat x file extension the same as y file extension | Sămărtean Rareș

Steps

open settings.json
1. in VS code UI: File -> preferences -> settings -> there should be a small button somewhere that lets you open the config file
2. in filesystem: home//.config/Code/User/settings.json
in settings JSON root, add "emmet.includeLanguages": {"x": "y"}