Support of macro resolver from JS code will allow webhooks to have much simple configuration. Now to get the state of the event (if it is a problem or recovery, get event source, get event update and event recovery data) we should add about seven fields just to pass event related macros to Webhook. And it is not like we are encouraging changing field value from macros to some predefined values.
So for the most part all the Webhooks require such macros:
If macro resolving can be done from JS there will be no need to add so many params to the form and that will make Webhook configuration much simplier for users (red fields could be removed):