This is a task to note (potentially unrelated) performance issues that were noticed while looking into T368405: Special:Homepage is rendered much slower (<1 sec to 2+ sec).

• Message::text is expensive, but being called a lot for Mentor default intro-messages that are never being displayed. => only call ::text when actually needed for display
• NewcomerTasksCacheRefreshJob seems to not do what it intends to do, because instead of refreshing the cache, it sets 'useCache' => false which in turn causes its result to not be stored in the cache.
• When changing the topics or tasks via the UI and saving the changed state, the cache should be regenerated. Currently, reloading Special:Homepage after changing the topics results in a cache miss in the main part of the request.

It might make sense to create dedicated tasks for them when they are being worked on.