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I'm trying to make it so certain text and images on an HTML page cannot be highlighted with the cursor, so it appears as if they're a part of the background.
Thanks! I searched but didn't find that in the results since it used "unselectable" instead of "unhighlightable".
Once it is rendered to the client browser area then the whole thing comes under the control of the user. Just to additionally clarify... If it's hosted on your website, and there is no authentication necessary to retrieve it, it can be found, and it can be downloaded. Even if you never link to an image anywhere, or use it in a webpage, or put it in an obvious place. If you can get to it over the internet without authentication, anyone can. The only caveat to that would be if you used strong encryption in combination with strong steganography. But even then be careful.