The ultimate guide for faster Drupal: Part 1 Caching
Performance
512KB Club
Auto-Generated Social Media Images | CSS-Tricks
Web Performance Heatmap Generator
HTML Size Analyzer
SpeedCurve | Ten years of page bloat: What have we learned?
Best practices for fonts
Embedding Youtube Videos in a Performant Way
Why you should be testing your 404 pages web performance
Increasing Application Performance with HTTP Cache Headers | Heroku Dev Center
Creating static social share buttons
Identifying, Auditing, and Discussing Third Parties – CSS Wizardry
patrickhulce/third-party-web: Data on third party entities and their impact on the web.
Explain like I'm five: Web Performance Optimization
Performance Implications of JavaScript Errors
matomo-org/matomo-log-analytics: Import any kind of server logs in Matomo for powerful log analytics. Universal log file parsing and reporting.
nolanlawson/fuite: A tool for finding memory leaks in web apps
JavaScript Loading Priorities in Chrome
How to Improve Page Speed from Start to Finish (Advanced Guide)
Automating Resource Selection with Client Hints | Web | Google Developers
Using Web Workers - Web APIs | MDN
Get Ready for Priority Hints | Web | Google Developers
Fast and Responsive Hero Videos for Great UX
Core Web Vitals Checker | Calibre
Web Performance Metrics Cheatsheet
The Art of Deception, Lighthouse Score Edition—zachleat.com
State of the Web: Top Image Optimization Strategies - Analysis - HTTP Archive
Short basics of caching
Optimizing images on the web
How to read a WebPageTest Waterfall View chart