Never Use Free SSL

Never Use FREE Universal SSL Cloudflare and Its 3 Solutions [with Strong Proof]

Because any person can see all the sites attached to the Cloudflare account easily with SSL Checker.

Need Proof?

Check here: http://bit.ly/CloudFlareProof

[I am not saying without any proof, I tested with my sites, it was giving accurate information]

Also this information can be used for the wrong purposes. How?

Will you ever like that your competitors know your other sites? I am sure 99% would say NO. If you don't care, then I apologize, this post is not for you.
Your competitors will know your many other sites by checking WHOIS of each site via SSL Checker sslshopper.com/ssl-checker.html

[It doesn't work if your competitors have enabled WHOIS Protection, also bulk WHOIS can be checked]

Your competitor can check your site once a month to check either you make a new site, and then they can act accordingly.
Your competitors can steal the keywords with SEMRUSH or Ahref if that site, also they can check Backlink Data from different sites and can analyze how your competitor is playing a game in SEO.
It's useful data for the people who can do NEGATIVE SEO of your site.

Wanna avoid this? Here are three solutions:

Your every site must be attached to different Cloudflare accounts, and try to attach SSL after a day or two.
Use FREE Let's Encrypt SSL because it doesn't play a game like this, it is being sponsored by Google and other big leaders and Google is using Let's Encrypt SSL on its Blogspot (Blogger) in beta stage.

Beta Blogger exists here draft.blogger.com (Here you can enable SSL for your custom domain free by going to SETTING>BASIC>HTTPS.

Buy 5$ per month Cloudflare Dedicated SSL (Maybe Cloudflare wants people to buy its 5$ SSL due to this issue)

Note:

It doesn't mean all the sites being shown by above SSL Checker belong to that owner, but WHOIS can help you.

Cloudflare Universal SSL is shared among other sites as it acts like Shared hosting where many sites of many owners are hosted on the same server, the same goes for Cloudflare Free Universal SSL.