This is a paid asset, but now you can download Spine Professional Free.
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Spine pro v3.8.75
Purchasing Spine enables saving projects and exporting animation data, images, video and texture atlases. Your Spine license also grants you permission to use the Spine Runtimes in your games and applications. Please see the full license text for more information.
After completing payment you will receive an email with instructions to download the full version of Spine.
Professional
Spine Professional includes all features and empowers industry professionals to design advanced animations.
All future updates are provided, without any additional charges. Each named person using Spine Professional requires their own license. Businesses with more than $500,000 USD annual revenue require a Spine Enterprise license.