Hi Shamu
Singularity has a different problem than firestorm.
For Singularity, you can just detach and attach the cat again, and it will show up.
I also noticed that, at least in Singularity, the cat will not be visible anymore when dropped in world, after it was visible on screen. Moving out of view range and back in did make it visible again.
It's unclear for now what triggers this viewer bug to occure, since most huds are just working in both Singularity and older Firestorm viewers.
While strictly a viewer bug, it may be possible to create a workaround, if we know the cause.
Regards
KittyCatS