You can try sharing your ref link in twitter without the https before the link and just add a description there to copy paste it,if you are aiming at getting referrals.
Thanks for the suggestion, I deleted the https:// and put a space after the dot (freebitco. in), so people can copy and paste the link.
How do you say Twitter considers the Freebitco.in referral link to be malware? Nothing happens or comes out after you tweet.

What shortener link are you using? Because I just tried this one now and it works, well I'm still testing it to see if it can be deleted or not after a few hours.
When you try to tweet the referral link a different message displays:
We can't complete this request because this link has been identified by Twitter or our partners as being potentially harmful. Visit our Help Center to learn more.
But when you try to fix it at your profile description a message appears saying it's considered malware:
Description is considered malware
I've used shorturl.at. Right after posting it works perfectly, but when I checked again after few minutes destination was removed already and the short link redirected to the main official shortener page.