【JavaScript】Mutation ObserverでDOMを監視する
https://qiita.com/twrcd1227/items/182de980e821336756f7?utm_campaign=popular_items&utm_medium=feed&utm_source=popular_items
#JavaScript #jQuery #dom #React #MutationObserver

@simevidas

Later in the linked #HTTP203 episode, @jaffathecake talks about <script async> and its benefit over <script deferred> on large pages.

This includes #Wikipedia articles, where we use it since 2015 for faster time until elements are interactive (for late content we use delegate event handlers, #MutationObserver, or DOM ready).

Someone asked recently why we don't use deferred, I explained in more detail at:
https://phabricator.wikimedia.org/T325480#8528502

See also #MediaWiki docs:
https://www.mediawiki.org/wiki/ResourceLoader/Architecture#Front-end