With a fixed 100Mbps connection and assuming 2kB per HTTP request-response, you can hope to get one leak every 11 minutes and 6.6GB of traffic, which is a constant 5k requests/s.
Maybe if Google reassigns all its SHAterred ressources to doing that...
... and then I realize that we were talking about cloudflare and my mining bot a capcha.
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edit: correction. The bug was affecting only some pages with some content filtering options enabled, and was more prominent under some specific circumstances.
Hence why it only happens 1/3.3M in average. An attacker could allegedly leak data much more reliably if he was able to identify the patterns that are more likely to trigger leaks.
If you can find such a page already, just jump to the last step and avoid signing your work.
Cloudflare is serving up more than 100Mbps; the attacker only has to zero in on what's fruitful, which yields something far higher than the 1 per 3.3M Cloudflare sees serving millions of innocuous requests.