In T284251#7481872 @TheDJ " wrote
ResizeObserver & IntersectionObserver need to be manually disconnected, else they leak memory through their callback. This happens in all browsers."
https://twitter.com/jaffathecake/status/1405437361643790337
IntersectionObserver is supported in the latest versions of iOS Safari, *but* it can be disabled. For older devices running the latest iOS, it is disabled by default to improve performance.
https://twitter.com/OliverJAsh/status/1456231452870418437
Since we plan to use this more going into sticky header and table of contents work, now seems like a great time to look into these issues and provide some best practices, adapting existing usages inside MobileFrontend for lazy loading images and RelatedArticles as necessary.
Outcome
- Get data around impacted users that are using older devices. What % of users are impacted by the Safari preference?
- Understand the memory leak problem and check if we are impacted.
- Document any changes we need to make to existing code if necessary in a single Phabricator ticket.