I downloaded https://github.com/EsotericSoftware/spine-runtimes/tree/3.8 to test is my local.
I ran /spine-ts/canvas/example/index.html it ok. BUT
When I change my data I don't know why this problem appears.
Note: My data when I viewing at Skeleton Viewer everything is ok!
I tried searching on google but sorry I don't know what keyword to explain to it so I post it here.
That my problem.

View on HTML with this green color.

View on Skeleton Viewer

View on HTML with this green color.

View on Skeleton Viewer
Thanks 4 support