Feature request: Add identifier highlighting

[parasyte]

I like the identifier highlighting in https://www.w3.org/TR/vc-data-integrity/. Clicking an identifier highlights it everywhere in the page making identifiers (e.g., variables and object properties) distinguishable from normal parts of speech and each other.

[danpape]

Yes! We found that especially helpful when going through the JSON-LD API algorithms. Check out the size of this one: https://w3c.github.io/json-ld-api/#algorithm-3