# Firefox Nightly Published articles for Firefox Nightly. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## Intent to Ship: JPEG XL DevFeed: [Intent to Ship: JPEG XL]() Original publisher: [Read original article]() Author: Jake Archibald Published: 2026-08-24T15:32:15Z Content type: article Language: en Sources: [Mozilla Hacks - the Web developer blog]() Topics: [Firefox](), [Web](), [Rust](), [Firefox Nightly](), [Google](), [Chrome](), [C++]() Tags: [blog](), [browser](), [browsers](), [c-plus-plus](), [developer](), [features](), [firefox](), [firefox-nightly](), [google](), [hacks](), [interop](), [mozilla](), [uncategorized](), [web]() ### AI overview Mozilla announces its intent to ship JPEG XL in Firefox, using Google Research's Rust-based jxl-rs decoder to provide secure, performant support. The article highlights progressive rendering and compares JPEG XL with AVIF for different image-compression use cases. ### Source excerpt It isn't often that new image formats land in browsers. In the early 2000s we had JPEG, GIF, and PNG. The 2010s gave us WebP, which was a modest step up from JPEG. But the 2020s have given us two new image formats that are a big step up from previous formats: AVIF and JPEG [...] The post Intent to Ship: JPEG XL appeared first on Mozilla Hacks - the Web developer blog. ## Trustworthy JavaScript for the Open Web DevFeed: [Trustworthy JavaScript for the Open Web]() Original publisher: [Read original article]() Author: Firefox Security Team Published: 2026-05-05T15:49:11Z Content type: article Language: en Sources: [Mozilla Hacks - the Web developer blog]() Topics: [JavaScript](), [Web platform](), [web applications](), [browsers](), [End-to-End Encryption](), [Encryption](), [Security](), [Firefox Nightly](), [Cloudflare]() Tags: [applications](), [browsers](), [cloudflare](), [encryption](), [firefox](), [firefox-nightly](), [javascript](), [meta](), [open](), [security](), [web](), [web-platform]() ### AI overview Mozilla presents WAICT, a web platform proposal for making client-side JavaScript more trustworthy when servers may be malicious or compromised. It binds delivered code to a developer-supplied manifest, records manifests in a publicly auditable log, and enables browsers to reject code that has not been logged. An early prototype is available behind a preference in Firefox Nightly. ### Source excerpt The open web is a critical platform for applications that handle highly sensitive data, from private communications to financial transactions and medical records. Traditionally, servers are trusted to deliver the appropriate code and resources for their web applications to browsers, who then provide a secure and isolated environment for their execution. In some circumstances, this [...] The post Trustworthy JavaScript for the Open Web appeared first on Mozilla Hacks - the Web developer blog. ## Experimenting with local alt text generation in Firefox Nightly DevFeed: [Experimenting with local alt text generation in Firefox Nightly]() Original publisher: [Read original article]() Author: Tarek Ziadé Published: 2024-05-31T16:43:46Z Content type: article Language: en Sources: [Mozilla Hacks - the Web developer blog]() Topics: [On-device AI](), [AI, ML & Data Engineering](), [cpu]() Tags: [ai](), [alt-text](), [artificial-intelligence](), [cpu](), [feature](), [featured-article](), [firefox](), [firefox-nightly](), [inference](), [machine-learning](), [on-device-ai](), [pdf]() ### AI overview Firefox Nightly is testing private, on-device AI that generates image alt text in its built-in PDF editor, with a longer-term goal of helping screen-reader users while browsing. ### Source excerpt Firefox 130 will introduce an experimental new capability to automatically generate alt-text for images using a fully private on-device AI model. The feature will be available as part of Firefox's built-in PDF editor, and our end goal is to make it available in general browsing for users with screen readers. The post Experimenting with local alt text generation in Firefox Nightly appeared first on Mozilla Hacks - the Web developer blog. ## Using color-mix() to create opacity variants DevFeed: [Using color-mix() to create opacity variants]() Original publisher: [Read original article]() Published: 2023-03-31T00:00:00Z Content type: tutorial Language: en Sources: [Una Kravets]() Topics: [CSS](), [color](), [Web Development](), [browsers]() Tags: [browsers](), [chrome](), [css](), [demo](), [experimental](), [firefox-nightly](), [guide](), [safari]() ### AI overview This tutorial explains how CSS color-mix() can create semi-opaque variants of brand colors by mixing them with the transparent color value. It also discusses browser support, color spaces, and a related DevTools demo. ### Source excerpt Build an alpha color system without splitting out channels using this one neat trick. ## New aspect-ratio CSS property supported in Chromium, Safari Technology Preview, and Firefox Nightly DevFeed: [New aspect-ratio CSS property supported in Chromium, Safari Technology Preview, and Firefox Nightly]() Original publisher: [Read original article]() Published: 2021-01-28T00:00:00Z Content type: article Language: en Sources: [Una Kravets]() Topics: [CSS](), [Chromium](), [Firefox Nightly]() Tags: [chromium](), [css](), [firefox-nightly](), [property](), [safari]() ### AI overview The article reports support for the new CSS aspect-ratio property in Chromium, Safari Technology Preview, and Firefox Nightly. The property helps maintain spacing in responsive layouts. ### Source excerpt The new CSS property that helps maintain spacing in responsive layouts. ## Back to Firefox (Nightly) DevFeed: [Back to Firefox (Nightly)]() Original publisher: [Read original article]() Author: Stanko Published: 2019-09-26T00:00:00Z Content type: opinion Language: en Sources: [Stanko Tadić]() Topics: [Firefox](), [Firefox Nightly](), [macOS](), [cpu]() Tags: [battery](), [cpu](), [firefox](), [firefox-nightly](), [issue](), [macos](), [rant](), [release](), [stable](), [version]() ### AI overview The author returns to Firefox after a MacOS scaled-resolution issue that caused very high CPU usage and battery drain was fixed. The fix was expected to reach stable Firefox 70 in late October 2019, while Firefox Nightly offered an earlier, potentially unstable version. ### Source excerpt Two years ago I wrote this rant. Firefox had a problem on MacOS on scaled resolutions, resulting in insanely high CPU usage and battery drain. Issue is finally fixed, and I'm happy to say I'm using it again. The fix is expected to land in the stable version in late October 2019, with the release of Firefox 70. Meanwhile you can download Firefox Nightly, which is the freshest (and sometimes unstable) version of Firefox. I'm really happy to be using Firefox again, and I think you should try it as well.