Test any page and see if it is using CloudFlare or not. Inspired by Feb 2017 Cloudbleed security incident.
Featured at Product Hunt: https://www.producthunt.com/posts/cloudbleed-indicator-for-chrome
Cloudbleed Indicator does not fix the issue, it recognises it using Google Public DNS (DNS-over-HTTPS).
If the cloud icon is bleeding, you might consider:
- changing your password,
- using 2-step verification (if available),
- leaving the site altogether.
Cloudbleed (also known as CloudLeak and CloudFlare Bug) is a security bug discovered on February 17, 2017 affecting Cloudflare's reverse proxies, which caused their edge servers to run past the end of a buffer and return memory that contained private information such as HTTP cookies, authentication tokens, HTTP POST bodies, and other sensitive data. Some of this data was cached by search engines.