: Spine -u 3.8.99 -i /path/to/skeleton.spine -o /path/to/skeleton-3.8.json -e json
: Some teams deliberately freeze their Spine version to avoid any functional drift. Once a specific 3.8.x patch has been thoroughly tested and proved bug‑free for their use case, upgrading to a newer patch (let alone a different major version) introduces unnecessary risk. For these teams, 3.8.99 is the final safe haven. Spine 3.8.99