Welcome to the forum.
This comes up with monotonous regularity and is already
covered in various threads. Search in the General Discussion forum.
I recently needed to copy something from an eBook and
couldn't copy it, so I took a screenshot. I can't think how you can
stop that.
Bottom line is you can make it difficult but there's always a
way around that can be found. Photograph the screen and OCR the
image if you are really determined.
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