Browser Compatibility Checker

Nested grid items participate in the parent grid tracks.

One-dimensional layout for distributing space along a row or column.

Two-dimensional layout with explicit rows and columns.

Set a preferred width-to-height ratio on boxes.

Spacing between flex and grid items without margins.

Elements stick within a scroll container until a threshold.

Snap scroll positions to defined points in a scroll container.

Select an element if it contains descendants matching a selector.

Match any selector in a list with shorter specificity rules.

Like :is() but always zero specificity.

Show focus rings only for keyboard-style focus.

Negate multiple selectors in one :not() expression.

Perceptually uniform color space for predictable gradients.

Mix two colors in a chosen color space in CSS.

Define reusable --token values with cascade inheritance.

Use the computed text color as a fill or border value.

Fluid values bounded by minimum and maximum sizes.

Single font files with adjustable axes like weight and width.

Truncate multi-line text after a set number of lines.

Balance headline line lengths for nicer rag.

Promise-based HTTP requests replacing XMLHttpRequest.

Syntactic sugar for promise-based asynchronous code.

Safely access nested properties when intermediates may be null.

Default values only when left side is null or undefined.

Await promises at module top level in ES modules.

True private fields on class instances.

Deep-copy structured data including typed arrays and Dates.

Relative indexing including negative indices.

Safer own-property check than hasOwnProperty.call().

Match patterns preceded by a fixed-width lookbehind assertion.

Observe element visibility relative to a root for lazy loading.

React to element content-box size changes.

Watch DOM tree and attribute mutations asynchronously.

Define reusable autonomous HTML tags with JavaScript classes.

Encapsulated DOM and styles for web components.

Native modal and non-modal dialog with ::backdrop.

Top-layer popovers with popover attribute and showPopover().

Server-render shadow roots with a <template shadowroot>.

Key-value string storage persisted per origin.

Structured transactional database in the browser.

Request/response cache used by service workers.

Key-value storage cleared when the tab closes.

Full-duplex communication channel over a single TCP connection.

Programmable network proxy for offline and push workflows.

Push notifications from a server via service workers.

Send analytics on page unload without blocking navigation.

Readable and writable byte streams for incremental I/O.

GPU-accelerated 2D/3D graphics with GLSL ES 3.00.

Modern GPU compute and rendering API succeeding WebGL.

Immediate-mode 2D drawing to a bitmap surface.

Render to canvas in a worker without DOM coupling.

Apply blur, color matrix, and other filter primitives in SVG.

Peer-to-peer audio, video, and data channels.

Append media segments for adaptive streaming players.

Floating always-on-top video window.

Low-level audio/video encode and decode in JavaScript.

Subtle crypto for digest, sign, encrypt in secure contexts.

Programmatic access to stored passwords and federated credentials.

Enforce typed sinks to mitigate DOM XSS.