Gecko Web Runtime Client

Python page and browser client for a versioned Firefox-derived WPR runtime. It exposes pages, contexts, navigation, DOM access, screenshots, diagnostics, Turnstile and WeChat workflow adapters.

The native runtime is installed separately:

python -m gecko_web_runtime install-runtime --version 155

The runtime is held in a private GitHub Release. Automatic download needs access to childclm/gecko-web-runtime. The Python client depends on wpr-runtime-core for Worker lifecycle and protocol compatibility. Historical HTTP imports are retained through wpr-http.

Media capture

For a browser-played Widevine page, use AsyncMediaDownloader. It starts the Worker, provisions the caller's Widevine profile, enables bounded native H.264 capture, waits for playback progress, writes a checkpoint, and verifies the final MP4 with FFmpeg.

import asyncio
from pathlib import Path

from gecko_web_runtime import AsyncMediaDownloader


async def main() -> None:
    result = await AsyncMediaDownloader(
        "https://example.test/video",
        output_dir=Path("./media-output"),
        ffmpeg=Path(r"C:\\ffmpeg\\bin\\ffmpeg.exe"),
        expected_duration=2575.32,
        max_retries=1,
    ).download()
    if not result["completed"]:
        raise RuntimeError(result["attempts"])
    print(result["package"]["output"])


asyncio.run(main())

Set WPR_RUNTIME_DIR, WPR_WORKER_EXE, WPR_PERSISTENT_PROFILE_DIR, and WPR_ENABLE_CDM=1 before creating the downloader. Widevine is installed by Firefox's official GMP installer into the persistent WPR profile; no existing Firefox profile or component is imported. This requires the Worker build with runtime.widevine_start/status support (Runtime 155.0.8 or later). For a bounded smoke test of a longer page, use sample_seconds=120 instead of expected_duration. The downloader keeps a checkpoint.json; rerunning with the same output directory returns a completed result without starting another Worker.