v131 · css

Deprecation of CSS Anchor Positioning property `inset-area`

The CSSWG resolved to rename the `inset-area` property to `position-area`. See the CSSWG discussion here: https://github.com/w3c/csswg-drafts/issues/10209#issuecomment-2221005001. The new property name, `position-area`, as a synonym for `inset-area` shipped via https://chromestatus.com/feature/6567965055778816. This entry is for deprecation and removal of th

concepts

  1. inset-area removal

    The inset-area property is renamed to position-area. Existing CSS using inset-area logs a deprecation warning during the migration window.

  2. Migration side-by-side

    The same anchor + popover rendered with both properties at once — see which side still moves as you pick a direction.

  3. Codemod tool

    Paste CSS → migrate-in-place. Reports the number of call sites rewritten.

  4. Synonym window demo

    Both spellings render the same right now. Pick which spelling to use and watch the popover move.

why it shipped

With the CSSWG resolution on renaming the property to `position-area`, this deprecation will clean up the implementation in Chromium for a standards compliant feature.

references