March 2026 Web Platform Digest
March 2026 saw a substantial batch of web platform features reach the interoperability threshold for Baseline's Newly available tier, plus a sizable wave of established capabilities move into Widely available status. The new arrivals span typography, JavaScript iteration, streaming, networking, and report handling.
Newly available in Baseline
Seven features became interoperable across all core browser engines during the month.
Math typography and text indentation
The math value for the font-family property is now available, letting MathML elements render with fonts optimized for complex formulas—better spacing and glyph coverage for technical documents. Two new text-indent keywords also shipped: each-line extends indentation to lines following hard breaks like <br>, while hanging inverts behavior to indent all lines after the first, useful for bibliographies and editorial styles.
Iterator and stream improvements
JavaScript's new static Iterator.concat() method merges multiple iterables into one sequence, removing the need for nested loops or intermediate arrays when processing data consecutively. The Streams API now fully supports readable byte streams, enabling binary data to be read directly into developer-supplied buffers for more efficient memory handling in performance-critical applications dealing with large files or network payloads.
Networking and reporting
WebTransport brings low-latency bidirectional client-server communication over HTTP/3, supporting both reliable streams and unreliable datagrams for real-time workloads like gaming and live streaming. The Reporting API centralizes browser-level notifications—Content Security Policy violations, deprecation warnings, crash reports—delivering them to a configured endpoint for streamlined monitoring.
Widely available this month
A larger set of features completed the 30-month interoperability period required for the Widely available designation, meaning they're safe for production use without polyfills.
CSS layout and typography
CSS subgrid now allows nested grids to inherit parent track definitions, simplifying alignment across DOM levels. The contain-intrinsic-size property lets you set placeholder dimensions for contained elements, preventing layout shift during lazy loading. The @counter-style at-rule enables fully custom list numbering and bullet styles beyond the standard set.
On the text side, the hyphens property controls hyphenation behavior at wrap points, with none, manual, and auto modes, while hyphenate-character defines the character used at the break point. The image-set() function brings resolution-aware image selection to CSS, mirroring the srcset behavior used by <img> tags.
Media queries and device integration
Several media features expanded responsiveness options. The viewport's overflow-block and overflow-inline features let developers target how devices handle overflowing content, useful for distinguishing paged media from continuous screens. The update media feature exposes display refresh characteristics, helping differentiate fast-updating screens from e-ink or static displays. Device orientation events from gyroscope and accelerometer hardware also reached wide availability, enabling movement-responsive experiences.
Storage and loading
Via navigator.storage, the Storage API allows querying available quota and persistence settings, and lets sites request that data resist eviction under storage pressure. The <link rel="modulepreload"> relation accelerates module-heavy applications by fetching and processing JavaScript modules and their dependencies ahead of the critical rendering path.
Baseline targets in practice
Chrome's Rachel Andrew gave a talk at Web Day Out on pragmatic browser support decisions. The presentation, covered in her post on the future of the web platform, explains how raising your Baseline target unlocks more features while narrowing compatibility—and how aligning that target with a project's launch date can set realistic guidance. Andrew's view is that thinking of Baseline targets as points in time, rather than specific browser versions, encourages more forward-looking choices about interoperable features without sacrificing compatibility standards.
Community tooling: Baseline on Eleventy
Stu Robson documented how he integrated the Baseline status web component into his Eleventy-based site, conditionally loading it on articles discussing specific web features. The component itself is an open source, framework-agnostic element, so it works across site generators, not just Eleventy—useful for anyone documenting feature support who wants to quickly signal interoperability to readers.
If a feature you're tracking is missing from Baseline or you've found an issue with anything listed here, the web-platform-dx tracker is open for feedback to help prioritize upcoming work.
