Portable Googleless Chromium web browser to use for testing

Please recommend a web browser with the following requirements:

1. Windows 7-10 compatible.
2. Completely portable. Absolutely no registry writes or writing files outside of its own dedicated folder(s)/subfolder(s).
3. No tracking or analytics (or easy to completely disable before the browser is run).
4. Uses the Chromium web rendering engine.
5. Frequently updated with the latest Chromium engine (especially when Chromium has a security issue).
6. Includes WebRTC functionality.
7. No contact with any endpoints (such as Google or Microsoft) except the ones actually required to establish user-requested connections. An exception can be made if it downloads Google’s Safe Browsing list or something similar (but hopefully this can be disabled).

Optional: Support extensions/add-ons.

My goal is to use this for testing, including testing WebRTC.

I thought Ungoogled Chromium would do the job, but the Windows version does not appear to be portable.