Extract the moderator source ZIP into an empty directory and open a terminal in the folder containing build.py.

Use CPython 3.12.13 with zlib runtime 1.3.2. Verify with:
python -c "import sys,zlib; print(sys.version); print(zlib.ZLIB_RUNTIME_VERSION)"

Run:
python build.py

No pip/npm dependencies, Node.js, Java, credentials, network access, or other project checkout are required. The build uses Python's standard library, validates the included source hashes, applies the readable Opera adapters, appends the included export shim to the hash-pinned upstream lamejs 1.2.1 browser artifact, and writes only to the bundle's build/ directory.

Output: build/ytmp3x-opera-v1.0.0-candidate.zip
Expected SHA-256: 75c1c07580396b6d70ea7d35f3c55e86f5fe5d671ea5b7fe9388edcfc7feddd7

The script verifies every runtime file and the complete ZIP hash and exits with an error on mismatch. Exact reproduction was verified using the versions above.

All first-party extension code and Opera adapters are readable. The only minified dependency is lamejs 1.2.1 (upstream npm license: LGPL-3.0). Its original readable modules, unminified browser bundle, published minified artifact, license/notices, and exact 276-byte local export shim are included. Upstream: https://github.com/zhuker/lamejs ; release: https://registry.npmjs.org/lamejs/-/lamejs-1.2.1.tgz . This reproduction uses that verified upstream prebuilt artifact; it does not rerun or claim reproduction of the historical upstream minifier. See README.md and vendor/PROVENANCE.json for hashes and provenance.
