Servo 0.6 turns CSS Grid on by default, and a lot of sites finally line up

On October 9 the Servo team published its monthly recap: 0.6.0 contains the 417 commits that landed in August. The headline item is that CSS Grid is now enabled by default.

What “Grid by default” means

Until now, a site with a Grid layout rendered in Servo as if the layout had collapsed into a single column. With @nicoburns’ PR (#45621) moving Grid off the flag and onto the default path, the team posted before/after pairs: a typical Grid homepage like rustweek.org, and labs.jensimmons.com, a demo that doesn’t look like it uses Grid but leans on it everywhere.

For a rendering engine, Grid is the fourth layout algorithm after block, float and absolute positioning. It involves track sizing, two-way constraint solving for min-content / max-content, and interaction with writing-mode. Turning it on by default usually means the layout framework can carry constraint solving rather than just stacking boxes top-down.

Web platform features that came along

A batch of smaller items landed too — the ones front-end developers will actually touch:

• touch-action: tells the browser who owns gestures in an area
• animation-composition: how multiple animations on one property compose
• color-scheme, plus <meta name="color-scheme">, so a page can declare light/dark support
• text-transform values full-width / math-auto / full-size-kana

The DOM side picked up interfaces people previously had to feature-detect around: requestAnimationFrame() on DedicatedWorkerGlobalScope, Location.ancestorOrigins, imagesrcset / imagesizes on <link rel=preload as=image>, CSSFontFaceRule.style, Request.isReloadNavigation / isHistoryNavigation, focusin / focusout events, new TextEvent(), and BaseAudioContext.createPeriodicWave.

The unglamorous part that matters

The notes admit something honest: this release reworked navigation, document loading and session history — the “who knew loading about:blank was so complicated” parts of the HTML spec. The upshot is that pages opening extra windows or embedding iframes work far more reliably. That work never shows up in a demo, but it is the line between “a rendering demo” and “a browser you could use daily”.

On security, Servo upgraded to SpiderMonkey v153 and fixed one behaviour: navigating away from a document that activated fullscreen now exits fullscreen. Compatibility fixes include locking touch panning to the dominant axis and a crash on gumroad.com.au. Accessibility keeps progressing behind --pref accessibility_enabled and now reports positions and sizes for items in the content tree.

The judgement

Grid by default is Servo’s coming-of-age moment, but don’t read it as “you can drop Chrome”: what decides usability is WPT pass rates and long-tail compatibility on real sites, and Servo is still climbing both. The trend is what’s worth watching — an independent Rust engine is filling in the hardest part of a layout engine.

Source: the Servo blog, “August in Servo: CSS Grid, text selection, and more!” (2026-10-09).