Invisible Firefox Mode (interest check)

[feder-cr]

hey, before building it i wanted to check if there'd be interest in an optional Firefox-based stealth mode for SeleniumBase, parallel to UC Mode and CDP Mode (both Chromium-based today). selected via config, no change to defaults.

motivation: UC Mode and CDP Mode cover the Chromium-stealth path very well. Firefox is already a first-class Driver option in SeleniumBase, but there is no Firefox-stealth equivalent today. sites that flag Chromium UA by default would benefit from a Firefox-side fallback.

the backend would wrap feder-cr/invisible_playwright, which drives a patched Firefox 150 (feder-cr/invisible_firefox, MPL-2, same license as Firefox upstream, fingerprint patches at the C++ source level so no JS shims to detect). drop-in compatible with the existing firefox.launch() interface, no connect_over_cdp needed. issues against the backend route to feder-cr/invisible_playwright.

also opened a draft PR (link TBD, will edit once created) with a proposal doc in help_docs/ so the idea has somewhere concrete to land.

[mdmintz]

I'll take a look at the repo. Maybe I'll learn something. Right now there's a Chromium focus for stealth, so I probably won't add anything for Firefox stealth at this time.