The last section of https://www.drupal.org/docs/8/api/cache-api/cache-api#s-cacheability-on-... → , added in the most recent revision of that page, looks spammy to me.
The profile page https://www.drupal.org/user/728128 → shows this user has been on d.o for 15 years, and is credited on one issue. Yet it claims, under Drupal Contribution,
Some modules and patches. Now helping on the Cache API.
Active
Spam
I reverted the edit, since documentation pages are not for advertising what somebody is doing.
I will keep an eye on that account's activities.
@avpaderno:
Thanks for taking care of this.