Whitelisting the Opera Mini browser how? Asking Opera Mini to include a signature with requests? Based on user-agent? In any case, browser behavior can and will be copied by bad actors if doing so is a get-past-cloudflare-free-card. That's why it's not just browser, it's browsing habits based on your IP and location in addition to fingerprinting where appropriate in order to allow legitimate users to prove they're human via captcha.
Edit: even if you just mean whitelisting their proxy ip... that doesn't do much good either. It's like asking to whitelist tor - those IPs are blocked because a good amount of spam or malicious traffic originates from them, not because there are x0,000 users on each.
> That's why it's not just browser, it's browsing habits based on your IP and location in addition to fingerprinting where appropriate
Mini is a barely configurable hosted browser with one IP, one location, and one fingerprint. It doesn't return anywhere near full HTML/JS/CSS, but highly cut-down code generated by Opera's server. Unless somebody has found a way to hack that server, I'm at a loss as to what damage it could cause.
This seems to me a case of sloppy use of overly broad security tools.
Edit: even if you just mean whitelisting their proxy ip... that doesn't do much good either. It's like asking to whitelist tor - those IPs are blocked because a good amount of spam or malicious traffic originates from them, not because there are x0,000 users on each.