Just do a screen capture instead.
You could also try copying the link, then paste into a new browser window before you save. If you try to save a photo from some websites like Flickr like that, they won’t let you do it if the owner of the photo limits usage rights.
I never go to those websites, I just am using google images. This all just started two days ago. I’ve been right clicking on photos and saving them since I got the IPad 3 years ago.