Razorback Invulnerability - Still a thing?

[Gryphen]

How is it that even after all this time, going in to carry out the Razorback Mission you find yourself still facing an Invulnerable Razorback, the poor old Bursa still can't damage the Razorback, and so all you do is waste yet another Razorback Cipher you crafted, what a waste of time this is... C'mon DW.. fix it once and for all.

[Nekomian]

It's probably multiple things that cause it, all jackal variants seem to be rather buggy in this regard; do you have any specific steps you took during your mission to make it invulnerable, or were you using specific frames? I'm seeing reports of Qorvex's abilities doing damage and bugging out bursas interacting with it, as an example.