The 'strict' and 'content' keywords for the 'contain' property used to include 'style'. Per CSSWG resolution and spec change this is no longer the case.


No other browser ships style containment, Firefox were reluctant to ship due to usefulness of counters containment and compat with Chrome, and the CSSWG resolved to remove style from 'strict' and 'content' which has been reflected in the specification.



Specification link

Specification being incubated in a Community Group

Status in Chromium


In development (tracking bug)

Consensus & Standardization

After a feature ships in Chrome, the values listed here are not guaranteed to be up to date.

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Search tags

css, contain,

Last updated on 2022-04-19