[raztoki]

Then no, not really. now, yes slightly more so in the detection/prevention of access within a challenge event. It prevents non standard browser access more so than specific to just JD Browser.
The detection methods back when was just entry traffic into said website, and totally out of your control as it was backend analysis.
So once a protection event happened they typically issued a challenge, first mode was just a simple javascript function, second mode was recapthca.

How I recall it previously working, Cloudflare initiate a block until challenge is complete, this can be for
- global attack
- geo/regional specific
- from collective exit points for example VPN, or TOR. This was/is deemed as not normal traffic, and typically as result they had to answer recaptcha more often.
- setting/config, website admins sometimes enforce it for some reason js or recaptcha

And as Psp indicated user-agent will not fly. It used to play no influence even when support worked.

I have not really looked into the latest Cloudflare, other than following some others trying to figure it out. A little information from Cloudflare themselves, I did read that they introduced AI backend. I find 'AI' over used term like 'cloud', so the extent of their AI backend I have no idea really. I haven't the time to focus on JD as I used to, but it would be nice to support Cloudflare again. Our presence was never negative to the platform (we never produce DDoS like events in the traditional sense) it would have actually complemented, even though we are semi automated program/workflow.

hope that helps