Red flags for websites

1. Won't work without javascript enabled
2. Won't work without flash enabled
3. Targets messages towards and/or denies entry to adblock users
4. Infinite scrolling instead of numbered pages
5. Splits a small article into multiple pages to generate more clicks and/or display transitional ads
6. Contains 40MB of javascript moving elements and other bloat cancer when the information the user is looking for is no more than 5-10KB in size
7. Opens popups without the user's request
8. Disables right-clicking
9. Will not let the user directly save media such as images or video
10. Embedded social media buttons
11. Embedded Google-anything
12. Makes the user consent to being tracked before being allowed to access a page

without proper certificate

What is "proper certificate" even supposed to mean?
Does it mean revoked? Using a broken algorithm? Using NSA curves? Using a RSA/DSA/DH bit length less than 2Kio? Using a broken or almost broken hash algorithm to sign the cert? Using static DH certs?

the https causes

The https protocol (http over tls) causes nothing of that sort.

It is illegal to not warn of cookies

[citation needed]

Why would you enter a illegal site ?

gelbooru/danbooru/exhentai/pixiv are all illegal in many countries such as the uk and canada as well as in some states of USA. I can however think of many reasons of why you would wish to use them.
Moreover illegal does not mean bad, all of the above sites are good.