NoPoW par 49016

This extension simply sets the user agent to a non-browser user agent when it encounters a PoW captcha. It does this by checking if a request contains a signature of a PoW captcha, and if so adds it to a whitelist, and whitelisted sites get a fake user-agent header, which completely bypasses the checks. This also makes sites using those captchas work without JS again.

Currently supported:
- Anubis (fully: a non-JS challenge was announced to be released only in the commercial version, once that releases this will also be added if the current bypass doesn't work with it!)
- go-away (partially: it's not too aggressive, has much more sensible defaults, and mostly uses non-JS challenges; some checks can still be skipped, but some actually block as intended though and cannot be skipped!)

Usage instructions: Install the extension, sit back and relax. The extension automatically detects PoW gates, and activates and refreshes the page if a PoW captcha is detected; no user interaction is required!