How to Create Screenshots in Firefox
Firefox's developer tools have been well-noticed due to the wealth of functionality they provide, but one tool you don't hear too much about is Developer Toolbar, which looks much like the console but serves a completely different purpose. One of those purposes is allowing developers to create a screenshot of the current page in Firefox. Let me show you how!
The first step is opening the Developer Toolbar with SHIFT+F2. Once the Developer Toolbar is open, you can direct Firefox to take a screenshot of the current viewport with the following command:
You can pass an additional configuration argument to get a screenshot of the entire page of the page:
screenshot homepage.png --fullpage
When these statements are executed, the image is saved to the browser's default download directory!