Why has right-clicking a preview image been disabled?

So today, the newest update hit me after a computer crash. I'm not too fazed about the design differences, but one thing did happen: I am not able to right click the in-chat preview of embedded images anymore. I have to left-click it to get the pop-up preview, and click "open original" then. But why? I don't want the pop-up preview. It's usually no great help. I just want to get to the full picture, in one single step.

Other Firefox users have reported the same thing, though someone on the desktop app has had no problems with that. So, is that a bug or a feature? Hard to tell, sometimes.