tekitou

This forbid visitor to download images. 
That’s all.
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Image Protector

strawman sockpuppet

Scott Werner

By default, WordPress links images to themselves. A user sees that the image is a link, clicks it and they are then taken to a page of just the image. Then they click ‘back’ in their browser or move on to another site.
You could manually remove the link, but that is a pain. Plus, when handing sites over to clients they shouldn’t have to remember to remove it to have a great functioning site.

No Image Link

Defaults the Image Link option to 'none' when adding a picture to a page or post.

Image Protector vs No Image Link