Hi there,
This is very weird so I don't know if it's me doing something wrong, but I don't think so.
I have Auto Key activated, I move a bone and then its key icon changes to orange, not red. And indeed when I switch to another frame and return to the one I've made the changes, the modification is gone.
But even more weird is that if I press Ctrl+Z, that modification I can't see seems to be undone.
I obviously don't remember this happening before I updated Spine today (to 3.6.17-beta).
Is it happening for you also?
Thank you.