I got an email about that but assumed it was simply a scam/phishing trip. After all if your links are like:
https://u2389337.ct.sendgrid.net/wf/click?upn=08onrY...
WTF do you expect any reasonably paranoid software developer to do? I kind of assume it is the more paranoid ones who actually care enough to check their code for programming bugs using the service in the first place, but I may be wrong.
Biting the hand that feeds IT
