Zip.js Files

New features

• Add the strictness option ("strict" | "balanced" | "tolerant", default "balanced") and maxAppendedDataSize option to ZipReader, controlling how appended data, prepended stubs, and ambiguous end-of-central-directory records are handled. checkAmbiguity: true is now an alias for "strict".
• Add createOPFSTempStream() and the createTempStream writer option to spill large buffered entries to the OPFS instead of memory, with an optional dispose() hook released on every exit path.
• Add FS#exportFileSystemHandle() and ZipDirectoryEntry#exportFileSystemHandle() to write an entry tree out to a FileSystemDirectoryHandle.

Security: End-of-central-directory selection

• Select the last end-anchored record that points to a central directory instead of the first signature scanned from the end; refuse genuine comment-cloak polyglots with ERR_AMBIGUOUS_ARCHIVE.
• Rank record reachability so empty or saturated bytes at the end of a comment can no longer forge a second record; genuine empty and zip64 archives still open.
• Prefer the reconciled central-directory offset over a stale one, so an identical-layout append remnant exposes the appended directory rather than the previous one.
• Apply the reachability check to the fallback scan, so a stray signature in appended data no longer hijacks recovery under tolerant. Security
• Bound the reachability probes to prevent a comment stuffed with unreachable records from amplifying into thousands of (potentially remote) reads on random-access readers such as HttpRangeReader.

Performance

• Speed up CRC-32 with a slice-by-8 implementation and by harvesting the CRC from the gzip trailer on the native CompressionStream.