GoKawiilHello friends! In August Ladybird gained video playback on Twitch, more video formats on YouTube, CSS scroll snap, JavaScript debugging in DevTools, downloads you can pause and resume, and session restore. It’s also the month engine performance went from occasional attention to a sustained focus, with a new style engine, layout caching, and CSS animations moving off the main thread. We added caging for cell pointers stored in JavaScript values, and CSS parsing and the painting pipeline moved to Rust.
Ladybird is entirely funded by the generous support of companies and individuals who believe in the open web. This month, we’re excited to welcome the following new sponsors:
Arnav Guleria with $5,000
You can see everyone currently supporting the project on our sponsors page, and we’re grateful to all of them. If you’re interested in sponsoring, please contact us.
Video on Twitch, and more formats on YouTube
Our implementation of Media Source Extensions gained support for fragmented MP4, as well as the AVC (H.264), HEVC (H.265), AV1, and AAC codecs, with support queries now communicating our real capabilities (#11251). This allows us to play adaptive-bitrate video on many more sites, including Twitch and Plex. YouTube already worked in Ladybird since all videos are available as VP9/Opus in WebM, but some older/less popular videos only have multiple quality levels in AVC, and higher qualities (especially 8K) are often only served as AV1.
We also fixed a batch of playback bugs: hovering YouTube’s video-card previews no longer crashes (#10992), players using preload="none" no longer hang (#11454), and HLS.js-based players start playing (#11480).
CSS scroll snap
Scroll snap landed (#10944): scroll-snap-type , scroll-snap-align and scroll-snap-stop . Wheel, keyboard, scrollbar dragging, touchpad flings and programmatic scrollTo() all snap, and content re-snaps when layout changes. ( scrollIntoView() doesn’t snap yet.) Carousels and full-page scrollers are built on this.
You can now debug JavaScript in Ladybird: set breakpoints, step through code line by line, and evaluate watch expressions (#11128), built on new breakpoint support in our JavaScript engine (#10936). Wasm debugging and DOM mutation breakpoints are still missing, but the core workflow works. (As before, the Firefox DevTools frontend is a stopgap until we build our own.)
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