Script Loading and Performance
Understand what a browser does when it meets a script, why JavaScript is the most expensive kind of file, and how to load it without blocking the page. Includes a script order lab and a script weight lab.
Understand what a browser does when it meets a script, why JavaScript is the most expensive kind of file, and how to load it without blocking the page. Includes a script order lab and a script weight lab.
Learn how the async attribute works, why it suits independent scripts like analytics, and why it causes flaky bugs when scripts depend on each other. Includes a race condition simulator and a which-mode quiz.