This is a placeholder QA ticket for ensuring the usability improvements we'll be introducing through tickets like T269950 are not "leaking" onto the page as a result of the parser cache split being removed in T280599.

Testing instructions

Testing environment

• Beta Cluster

Scenarios to test

1. People who have the yet-to-be-created readability enhancements setting [i] ENABLED within Special:Preferences#mw-prefsection-editing-discussion should see topic containers (T269950), new reply and topic affordances (T255560 + T267444) etc.
2. People who have the yet-to-be-created readability enhancements setting [i] DISABLED within Special:Preferences#mw-prefsection-editing-discussion should NOT see topic containers (T269950), new reply and topic affordances (T255560 + T267444) etc.

Meta
The "Feature visibility" requirements above should not be affected by whether an individual manually configured a particular setting or whether the wiki as a whole configured the setting in a particular way for all users.

i. T270316