GitHub Source Marker Bug

While reviewing the code on GitHub, I saw that the source marker marks a ready-made function in Node.js. This bug can be resolved.

EDIT
1: https://imgupload.io/images/2021/05/13/Screenshot_1.png
2: https://imgupload.io/images/2021/05/13/Screenshot_2.png

Are you looking for the repository of the syntax highlighter used by GitHub to highlight code in its WebUI, so that you can submit a bug fix for the JavaScript syntax defiiniton?