If you are not sure if the website you want to visit is safe, you can check it out here. Enter the address (url) of the website and see the invisible elements, such as a header or meta data.
site address:www.youtube.com/yts/img/pixel-vfl3z5WfW.gi...
Url ContentGraphics Interchange Format
MIME Type / Internet Media Typeimage/gif
MIME Type image
File Extension.gif
More Details (link to:)Wikipedia: Graphics Interchange Format
Powered by: Very Tiny URL Shortener at https://vturl.net VeryTinyURL

Header

HTTP/1.1 200 OK
Accept-Ranges bytes
Content-Type image/gif
Vary Origin
Timing-Allow-Origin htt????/www.youtube.com
Content-Length 43
Date Wed, 15 Nov 2017 03:35:12 GMT
Expires Thu, 15 Nov 2018 03:35:12 GMT
Last-Modified Mon, 13 Nov 2017 15:00:25 GMT
X-Content-Type-Options nosniff
Server sffe
X-XSS-Protection 1; mode=block
Cache-Control public, max-age=31536000
Age 527693

Load Info

page size43
load time (s)0.005039
redirect count0
speed download0
server IP216.58.208.238


* all occurrences of the string "http://" have been changed to "htt???/"