• Change Array by copy proposal:
  • Moved to Stage 3, March TC39 meeting
  • Disabled forced replacement and added /actual/ entry points for methods from this proposal
  • Array.prototype.toSpliced throws a TypeError instead of RangeError if the result length is more than MAX_SAFE_INTEGER, proposal-change-array-by-copy/70
• Added some more atob / btoa fixes:
  • NodeJS <17.9 atob does not ignore spaces, node/42530
  • Actual NodeJS atob does not validate encoding, node/42646
  • FF26- implementation does not properly convert argument to string
  • IE / Edge <16 implementation have wrong arity
• Added /full/ namespace as the replacement for /features/ since it's more descriptive in context of the rest namespaces (/es/ ⊆ /stable/ ⊆ /actual/ ⊆ /full/)
• Avoided propagation of removed parts of proposals to upper stages. For example, %TypedArray%.prototype.groupBy was removed from the Array grouping proposal a long time ago. We can't completely remove this method since it's a breaking change. But this proposal has been promoted to stage 3 - so the proposal should be promoted without this method, this method should not be available in /actual/ entries - but it should be available in early-stage entries to avoid breakage.
• Significant internal refactoring and splitting of modules (but without exposing to public API since it will be a breaking change - it will be exposed in the next major version)
• Bug fixes:
  • Fixed work of non-standard V8 Error features with wrapped Error constructors, #1061
  • null and undefined allowed as the second argument of structuredClone, #1056
• Tooling:
  • Stabilized proposals are filtered out from the core-js-compat -> core-js-builder -> core-js-bundle output. That mean that if the output contains, for example, es.object.has-own, the legacy reference to it, esnext.object.has-own, no longer added.
  • Aligned modules filters of core-js-builder and core-js-compat, now it's modules and exclude options
  • Added support of entry points, modules, regexes, and arrays of them to those filters
  • Missed targets option of core-js-compat means that the targets filter just will not be applied, so the result will contain modules required for all possible engines
• Compat data:
  • .stack property on DOMException marked as supported from Deno 1.15
  • Added Deno 1.21 compat data mapping
  • Added Electron 19.0 and updated 18.0 compat data mapping
  • Added Samsung Internet 17.0 compat data mapping
  • Added Opera Android 68 compat data mapping