In an attempt to rectify the the bucketing imbalances identified in T291308, we will use this ticket to improve tracking for logged-out users who're doing full-page wikitext editing.
Minimum test case
This can be tested in the normal ways of watching for EditAttemptStep events -- just verify when doing full-page wikitext editing on a talk page (WikiEditor and NWE, logged in and out) on an abtest wiki that the bucket and (if logged out) anonymous_user_token fields are present on the event.