We get almost 99% of our user above TLS 1.2. But when user reach via TLS 1.3 page view ratio is 40-50% more than when user reaches via TLS 1.2.
TLS 1.2 is not that slow to have such a drastic effect on pageview ratio. Is there any known issue in Cloudflare. Can you please check your own stats and see if chrome above 70 version and less than 70 version has different page view ratio in Google Analytics Stats?
This may be a form of “selection bias”, I would bet most crawlers don’t use TLS 1.3 yet, but Chrome updates are fast-tracked so more real users will visit with the newer protocol.
Have you checked the break down stats for browser user agent vs ssl protocol (TLS 1.2 vs TLS 1.3) as Chrome isn’t the only web browser that now supports TLS 1.2/TLS 1.3 also check breakdown stats for device connection i.e. desktop vs mobile/tablet and your page speed metrics like domcontent loaded and dom interactive and average page load times. You may find that the more pageviews per user ratio are over higher speed connections where page load speed metrics are faster too.
But TLS 1.3 does save 1-RTT round trip time so is faster so faster page views lead to probably more user activity. Also if your origin web server supports TLS 1.3, that’s another 1-RTT saved for CF to origin connections as CF now supports connecting to your origin over TLS 1.3 too if your origin supports TLS 1.3.
Last I checked Cloudflare does not support TLS 1.3 from Cloudflare to Origin. They are stuck at TLS 1.2.
Enabling TLS 1.3 via Cloudflare does not require your origin web server to support TLS 1.3. Furthermore, Cloudflare does not currently support TLS 1.3 from our edge to origins.
from my Nginx logged ssl protocol/cipher stats filtered to exclude known bots I can see all my CF to origin Nginx connections communicating over TLS 1.3
I you can see from my above logged stats no, CF edge to origin is over HTTP/1.1 but supports TLS 1.3 if your origin server supports TLS 1.3 final RFC revision and not the older TLS 1.3 drafts.