pypi / soupsieve

soupsieve

What changed in soupsieve 3, from its official release notes, upgrade guides and advisories. Sources checked 2026-10-28.

2 breaking1 performance9 fixes and other

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npx @unstale/cli init

soupsieve 312 changes

Only non-ASCII identifier code points remain unescaped; all other non-ASCII characters are escaped, as defined by the CSS specification.
3.0.4release notes
Soup Sieve 3.0+ requires Python 3.11.5 or later because earlier versions have broken possessive quantifiers.
3.0.2release notes

Caches resolved directionality when matching :dir() to avoid quadratic time on deeply nested dir="auto" elements.
3.0.4release notes

Unescaped U+0080–U+009F characters in identifiers are allowed to match browser behavior.
3.0.4release notes
Elements with dir="auto" or <bdi> and no strong direction characters are assumed left-to-right, rather than inheriting the parent's direction.
3.0.4release notes
Prevents :in-range and :out-of-range from raising ValueError for week inputs whose week-year is 10000 or greater.
3.0.4release notes
Corrects :in-range and :out-of-range handling of time and datetime-local values that include seconds.
3.0.4release notes
Corrects matching for :nth-last-child(an+b of S) when the first sibling tested does not match S.
3.0.4release notes
Numeric input ranges match correctly when values or bounds use scientific notation.
3.0.4release notes
Keeps own and descendant text separate when combining :soup-contains() and :soup-contains-own().
3.0.4release notes
When matching with >, the BeautifulSoup object no longer counts as a parent.
3.0.3release notes
Relative sibling matching under :has(~) no longer incorrectly matches a sibling that came before the target element.
3.0.3release notes