Disable the Heartbeat API Except in the Post Editor
Keeps the Heartbeat API (autosave and post locking) in the editor but turns it off on every other admin and front-end page to save server requests.
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.
Load Selected Stylesheets Without Blocking Rendering
Loads the stylesheets you choose in the background so they no longer delay the first paint, ideal for CSS of things below the fold like sliders or forms.
Move Selected Scripts to the Footer
Moves the scripts you list from the page head to the footer, so they stop blocking the page from rendering.