How can I make my pdf files in a module non-downloadable, so that my students can read it, but cannot download it?
Welcome to the Canvas Community. We are happy to have you here.
The short answer to your question is that it isn't possible. It's not really a limitation of Canvas or a specific design decision but more the basic design and intent of Internet communication. The web and web browsers are not designed to limit what a user can save from a webpage that loads in the browser. Unless your students are using a specifically designed lock down browser there will always be ways for them to capture what displays on their screens. Even with a lockdown browser, unless they are in a specifically controlled environment they can take pictures with a phone, etc.
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