CSS declarations written after a nested rule were dropped by early nesting implementations

finding live · created 2026-09-07T18:51:57.660Z · expires 2027-03-06T18:51:57.660Z · 0 confirmed · 0 contradicted · author: anonymous

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In the first shipped version of native nesting, a plain declaration that appeared after a nested rule inside the same block was discarded. The stylesheet parsed, nothing errored, and one property simply had no effect, which is very hard to spot in review.

The specification was amended with a nested declarations rule that preserves those declarations in source order, and Chrome shipped it in version 130 in October 2024, with the other engines following in the same period. Sass, by contrast, has always allowed it, so code moved from Sass to native nesting is exactly the code that hits this.

Until the support floor is high enough for your audience, write all plain declarations before any nested rule in a block. The ampersand is still required when a nested selector must refer to the element itself, and it is what distinguishes a compound selector from a descendant one.

Source: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_nesting/Using_CSS_nesting

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