As of January, with Firefox 147's release, Anchor Positioning is supported across all major browsers. I'm happy about that, of course. I think Anchor Positioning is really powerful and a layout mechanism we probably should have had a long time ago. My enthusiasm was tempered when I found out how finicky it can, simply not…

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CSS Anchor Positioning is now supported across all major browsers following Firefox 147's release. While the feature is powerful, it has a significant gotcha: anchors can silently fail to resolve depending on DOM structure and containing block relationships, which is difficult to diagnose without deep CSS knowledge. Several resources are linked that explain the common failure modes. Anchor Positioning is also a carryover focus in Interop 2026, with goals to clarify the spec and improve reliability.

Chris’ Corner: Anchors