Bug Bounty, two years in
blog.twitter.com
blog.twitter.com
Me: here is a bug
Them: it's a feature, not a bug [fixes feature]
This behavior compromises the privacy of few hundred million users and circumvents your policy.
It is not XSS/CSRF and it is by design, your ticket is closed.
At least they did not fix it last time I checked.
Me: Here is a bug. Your implementation does X when the specification says that it should do Y. Here is the RFC and the relevant sections explaining how it should work [link].
Them: This isn't a bug. Reference to some other popular piece of unrelated software that also has a faulty URL implementation. Half-assed apology for creating an un-resolvable problem for you while implying that you're an idiot at the same time.
Side-note: Please, everyone stop writing your javascript URL validation with checks for "http(s)"
If they mind it being disclosed, it's probably not a feature.