Instant Mockup Generator – 2 Mockups

Great for making quick mockups. Even if you're a designer, I recommend Placeit – Brad Luttrell 5/5

Read more about Placeit's Mockup Generator

Firefox Browser Mockup in a Windows Desktop

The picture shows a web browser that is open but blank in front of a blue background. It shows a browser without a URL in it and it just has a blue background with a "upload your image" text on it. It also shows a 1200x900 px number on it as well. The background a light shade of blue.
Firefox Browser Mockup in a MacOS Desktop

A white Firefox browser with one tab opened. The browser has a blue background. There are red, yellow, and green buttons on the top left of the browser.