Great question -- Thanks for asking!
Since LeoJS is a VSCode (or vscodium) extension, its source code is compiled/minified somehow, and many other source files are omitted from the final 'distribution' package.
Therefore, the way to open and view LeoJS source files (or browse it's
Leo source file in Leo/LeoJS) is to clone the repo from
https://github.com/boltex/leojs, and look at the base of the project folder for
leojs.leo.
This would be the equivalent of LeoPyRef.leo. (and if you're looking for the equivalent of the base setting file, leoSettings.leo, its at the same place, and named
leojsSettings.leojs.
Hope this helps! 🦁
Félix