My spine version is 4.0.62
When I drag exported objects to Unity, I find texture have error about alpha.
This is spine exported texture open with Photoshop.
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This is spine exported texture show in Unity Inspector.
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This is spine animation in Unity.
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This is Spine Texture packge Setting.
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by the way, I can't active Spine material Straight Alpha Texture field in Unity, because it can't work on Mobile devices.(I only test in Android.)
This is Spine raw project.
SpineProject.rar