Highlighting vs Optional terms

Is it conceptually correct not to highlight a term when it has been searched for as an optional element?
In my case, the search: key1 ~key2, even if it returns documents containing the two keys in adjacent positions, only key1 is highlighted in the generated (SUMMARIZE) snippet.

Ambient: Redisearch 2.0

Thank you for all your excellent questions.
This behavior is currently expected as we consider only the first term found.
Please open an issue on GitHub, so when we get to change the behavior, we will treat the effect of optional terms as well.