Short answer: I don't know how to say bubblewrap in Chinese. Will float the question around though.

On the tech issue -- usually that error should be triggered if the title is substantively similar to something that has already been posted, as the title of the "post" in the system needs to be unique. Maybe there is a bug in the part of software that handles this, and it is coughing up blood on uncommon characters like ／ . Not sure....