change(image-optimization): AVIF reached Baseline widely available - #159
Draft
jdevalk wants to merge 1 commit into
Draft
change(image-optimization): AVIF reached Baseline widely available#159jdevalk wants to merge 1 commit into
jdevalk wants to merge 1 commit into
Conversation
webstatus.dev reports AVIF crossing to Baseline widely available on 2026-07-25 (low date 2024-01-25, Edge 121 being the last engine in). Corroborated against per-engine ship dates: Chrome 85, Safari iOS 16.1, Safari 16.4, Firefox 113, Edge 121. The page treated AVIF as the smallest-but-riskiest option to be layered behind WebP. That framing is now wrong: the remaining trade-off is encoding time, not support. Encode AVIF first; keep the <picture> chain, because "widely available" is a statement about browser versions released, not versions installed. Also repairs the sources, which carried no primary standard at all: - web.dev "Use modern image formats" (last updated November 2018, never mentions AVIF) no longer supports what the page claims. Dropped. - MDN <img> replaced by MDN's image file type and format guide, which is what a format discussion actually needs. - WHATWG HTML 4.8.4 Images added, and leads. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Deploying specification-website with
|
| Latest commit: |
026d092
|
| Status: | ✅ Deploy successful! |
| Preview URL: | https://ca0042ea.specification-website.pages.dev |
| Branch Preview URL: | https://change-avif-baseline-widely.specification-website.pages.dev |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
What changed
src/content/spec/performance/image-optimization.mdtold readers that "AVIF gives the smallest files but encodes slowly; WebP is well-supported and faster to produce", then showed a<picture>chain framed as offering fallbacks for AVIF. That framing treated AVIF as the format whose support you hedge against. It no longer is.The page now says to encode AVIF first, and names the remaining trade-off honestly — encoding time, which matters for user uploads and batch jobs but not for a build step. The
<picture>chain stays, with a sentence saying why: "widely available" is a claim about browser versions released over the last two and a half years, not the ones people are running.Why now
Daily standards scan, Baseline check.
webstatus.devreports AVIF crossing tobaseline_status:widelywith a high date of 2026-07-25 (low date 2024-01-25).Corroborated against per-engine ship dates before writing anything:
Edge was the straggler; the thirty-month clock from its ship date is what just expired.
Sources
The page carried no primary standard at all — MDN, two web.dev articles, and the HTTP Archive Almanac. Repaired as part of the same change:
<img>, added MDN — Image file type and format guide (path resolved through the MDN MCP), which is what a discussion of formats actually needs.srcset,sizesand<picture>.Kept: web.dev — Serve responsive images; HTTP Archive Web Almanac — Media.
Status
Unchanged at
required. Nothing here moves the bar — shipping enormous images still breaks the page for people on slow connections, which is why it wasrequiredbefore.Changelog entry — borderline, your call
Added
2026-08-04-avif-baseline.mdas achangedentry. This sits on the line: it is a real change to what we recommend on arequiredpage, but it is one paragraph rather than a rewrite. Happy to drop it if you would rather keep the changelog for larger movements.Re-date before merging if this sits for more than a day — both the entry's
dateand the filename, per the CLAUDE.md rule that entries are dated when they land onmain.Not bundled
The page's "Strip metadata" line advises removing EXIF and colour profiles wholesale. That advice now collides with content provenance (C2PA / Content Credentials), which is carried in exactly the metadata a naive optimiser strips. That is a separate topic and possibly a separate page — raised in the scan summary rather than smuggled in here.
npm run buildpasses.🤖 Generated with Claude Code