My new friend is backpic.twitter.com/qYCYpo0fw2
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Interesting, they are capturing your IP and then redirecting to the target URL.pic.twitter.com/tXvL2AMajc
Yes, this website is collecting: Time, IP address, Country, City, Device, Referring pages, Internet service provider, Device identificator and Proxy & redirectspic.twitter.com/1vF5WzeCUv
Use always VPN!!!!
Atleast he tried to get your attention 
No VPN ?
I always use Curl to check the location of shortened links. But, good news is that you can just grab his IP address from the email header.
Using cURL to get the value from the location header and not to redirect is one way to go. 
Yeah, anything but clicking on the link works well.
For URLs that aren't direct (redirecting), I use the site http://www.redirect-checker.org . Obviously, not ideal to use when it comes to emails as the links may have a tracker to confirm if the email is active.
Also, the site used for logging also logs the user agent. Since you can use a custom user agent, you could give them your own message that way. Heh.
How a link can be tracked?
If the spammer were to get hold of an email list (i.e. database breach), they may either have it in the GET parameter raw, hashed or it'll be an id associated with that email. If the victim were to click on the link, the spammer would then know that it's an actively used email.pic.twitter.com/JVI8mDXMlf
Seems quite intentional to me, not some naive bored person.
Man!! you should be careful and not trust anyone randomly. When you do the good work lot of people are going to come for you. I know its funny advising someone like you but still use virtual box with differ ip or use some kind of protection coz govt cn also come fr u.
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