Page Weight Summary in the Admin Bar
Shows an admin bar item on the front of the site with the total size of the page's scripts, stylesheets, images and fonts, and a breakdown with the heaviest files when you click it.
Snippet Library
Performance snippets for WordPress
Snippets that make WordPress lighter and faster: remove emoji scripts and embeds, control the Heartbeat API, limit revisions and load scripts only where they are needed. For developers and site owners chasing better Core Web Vitals.