We believe we found a bug in spine 3.8.99 Professional.
The importing of animation attachments into an existing skeleton (via either "replace" or ignore") doesn't work.
For example, for json like this
...
"animations": {
"victory": {
"slots": {
"eye_l": {
"attachment": [
{ "name": "chibi/eye_closed_l" }
]
},
"eye_r": {
"attachment": [
{ "name": "chibi/eye_closed_r" }
]
}
},
"bones": {
...
the "slots" part is ignored completely, leading to missing keys. The json was created in the same version of spine.
The only way to make sure they are imported is to import data as "New project/create a new skeleton" and delete the previous skeleton.