v0.1.26310 Sep 2026·Rendering, Web APIs & DOM

Object property rules, regular-expression objects, and function introspection

A deeper pass over how faithfully the engine follows the JavaScript standard for objects, regular expressions and functions. Defining a property on an object now enforces the rules the language requires: it reports a clear error for an invalid request (a bad target, a malformed description, or an attempt to change a property that was locked down) and records exactly which parts of a property are fixed, so code that inspects or guards its objects behaves the way it does in other browsers. Regular expressions now act like the standard objects they are: they expose their pattern and option letters through the same accessors other engines provide, always in the canonical order, and they carry the built-in hooks the language's text search, match, split and replace operations rely on. And functions now report their name and their number of arguments correctly to code that inspects them, which a great deal of library and framework code reads. None of this changes code that was already correct. The JavaScript language aspect moves 89 to 90; the overall platform score stays at 70.

Parity with the reference browser

74overall, as of v0.1.343

Web APIs / DOM surface42

Security architecture66

GPU / graphics acceleration68

DevTools / extensions72

Networking85

Media85

Accessibility85

Real-world site compatibility99

HTML parsing100

CSS parsing + selectors100

Layout: block / flex / grid / tables / writing-modes100

Paint + visual100

JavaScript language100

JavaScript performance (JIT)100

HTML parsing100

What changed 3 changes

Rendering	Defining object properties follows the rules. Defining a property now reports a clear error for an invalid request, such as a non-object target, a malformed description, mixing a value with a getter or setter, or trying to change a property that was fixed in place, and it records which parts of each property are locked, so code that inspects or guards its data sees the same result as in other browsers.
Rendering	Regular expressions behave like standard objects. A regular expression now exposes its pattern and its active option letters (always listed in the standard order) through the same accessors other engines provide, and it carries the internal hooks that the language's own text search, match, split and replace operations use, so more library code that reaches for them works unchanged.
Web APIs & DOM	Functions report their name and size to inspection. A function's name and its number of arguments are now visible to the code that inspects functions, not just readable directly, which a large amount of library and framework code relies on to label, route and validate.