CSS Anchor Positioning

[lukewarlow]

Request for Mozilla Position on an Emerging Web Specification

• Specification Title: CSS Anchor Positioning
• Specification or proposal URL (if available): https://drafts.csswg.org/css-anchor-position-1/
• Explainer URL (if available): https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/CSSAnchoredPositioning/explainer.md (probably slightly outdated but should give a general overview)

https://xiaochengh.github.io/Explainers/css-anchor-position/explainer.html

• Caniuse.com URL (optional):
• Bugzilla URL (optional):
• Mozillians who can provide input (optional):

Other Information

This new CSS functionality will allow web developers to position elements anchored to another element with built in fallback positioning. This will go hand in hand with the Popover API which Mozilla is positive on

[xiaochengh]

The original Microsoft explainer is very old and has a lot of out-of-date details.

Here's a new explainer: https://xiaochengh.github.io/Explainers/css-anchor-position/explainer.html

[zcorpan]

@emilio @dholbert

[dholbert]

We're positive on anchor positioning; it seems to be an elegant evolution of absolute positioning, with an assortment of nice use-cases.

I filed https://bugzilla.mozilla.org/show_bug.cgi?id=1838746 as a placeholder metabug to track implementation.

[jwatt]

Intent to Prototype e-mail:
https://groups.google.com/a/mozilla.org/g/dev-platform/c/4cbytMKbHtg

[steffchep]

What's the ETA on this feature? Asking for a friend.

[emilio]

https://bugzilla.mozilla.org/show_bug.cgi?id=1838746 is the right place to track implementation status.