Yes, you can.
If you want to use fullPage.js, for multiple websites you have to choose the Professional or Business licenses. These 2 licenses allow you to use the code on an unlimited number of domains, servers, and projects, regardless of the environment type (production, QA, etc.)
This is different from the OEM/SaaS license and the Hobby License. The hobby license is only valid for 1 domain. When using the OEM/SaaS license you'll need a license per project that requires distribution rights.
Bear in mind that this works differently for fullPage.js extensions, in which you'll have to purchase one or another license depending on the number of domains you want to use it for.
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