JPEG/ JPG files fail to open in new tab now, why?

Since the latest update, when I click on a link to an image containing a JPG (JPEG) file, now Firefox opens a new tab but it's empty, and it automatically downloads the JPG file, saving it in Downloads. To see the image, I have to go to Downloads and choose to open the file. I hate this. How does software get dumber like this? Someone messed up. It's not just some sites, it's all the time, so Firefox changed.

Is there a quick fix for this in Settings? I've been looking to no avail.