There are several ways to save Instagram photos you might want to refer to later. But if you want to download a full-resolution JPG version, and it's not your account, it gets a lot trickier.
Of course, this is by design - you didn't take the photo, so you probably don't have the copyright. Plus, Facebook, Instagram's parent company, would rather you save photos you like to its "Collections" feature.
There are several websites that allow you to download Instagram photos, but they're all unauthorised, and many have sketchy ads. Plus, they may potentially have malware and other shady tricks.
You can also take a screenshot of the Instagram post, but that results in a lower-resolution file.
So, you can take it into your own hands, and figure out how to download full-resolution Instagram photos - for example, earlier this week I wanted a photo of my cat that I uploaded years ago to a novelty account (I had since lost the original image).
Here's how you download Instagram photos in Google Chrome.
On the desktop version of Instagram, that menu button is on the bottom right.
On Chrome, you'll find it in View > Developer > View Source. (Firefox, Microsoft Edge, and Safari also allow you to view source.)
The text on this page is HTML, which tells the browser how to arrange the elements on the webpage for a viewer. It's not computer code, it's what's called "markup," or formatting, basically. It's not hard to learn to read HTML - here's a good place to start.
Use Control+F or Command+F and search for "JPG." It's usually the first link. Copy the link starting with "https."
You can save or download the photo from here by right-clicking on the image and selecting "Save Image As...". (The picture of my cat is a bit small, because it was uploaded years ago. Recent photos are often much larger.)
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