Hi @ydzenisiuk ,
Custom extensions built with Extension Manager for the Universal Editor are private to your AEM environment, as Adobe does not yet provide a public marketplace. To share them, you can distribute the code or package (e.g., via GitHub or zip), and others can manually install it through their own Extension Manager by uploading, deploying, and enabling it in their environment. In short, sharing is possible but manual, and for broader adoption you can raise a feature request (RFE) with Adobe for a public extension-sharing mechanism.
Thanks & Regards,
Vishal