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JavaScript Intermediate

ResizeObserver: Components That Respond to Their Own Size

Window resize listeners cannot see a sidebar collapsing or a panel being dragged wider. ResizeObserver watches the element itself - the JS half of container-based design.

Mar 16, 2025 2 min 526

JavaScript Advanced

Catching DOM Changes You Didn't Make: MutationObserver in Practice

When a third-party script injects, moves or mangles your markup, you cannot patch their code - but you can watch the DOM itself and react the instant it changes.

Mar 28, 2024 2 min 1,676

JavaScript Intermediate

Infinite Scroll Without a Single Scroll Listener

Scroll listeners fire hundreds of times per second and need throttling, math and luck. IntersectionObserver watches a sentinel element and calls you exactly when it matters.

Mar 19, 2024 2 min 1,720

Carlo Fontanos

ResizeObserver: Components That Respond to Their Own Size

Catching DOM Changes You Didn't Make: MutationObserver in Practice

Infinite Scroll Without a Single Scroll Listener