Hi @Markus291720795tz2!
HDRIs, models, images, and materials can be added by dragging and dropping the desired files into the assets > libraries panel. The libraries panel allows access to your Creative Cloud Libraries where you can organize cloud-synced content for use across applications, projects, devices, and teams.
https://substance3d.adobe.com/documentation/sg/assets-panel-213060323.html
*The libraries feature, however, is not available within Stager on Steam because it relies on services that are not available with the Steam licensing and platform.
https://substance3d.adobe.com/documentation/sg/stager-on-steam-238060043.html
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