Are you implementing a responsive design and are looking for an easy way to preview various screen sizes? If so, the Web Developer browser add-on is a great tool to have at your disposal. It can be downloaded here: http://chrispederick.com/work/web-dev…
Once installed, you can simply navigate to the “resize” tab on the add-on bar and select “view responsive layouts” to generate a preview of your page in various device widths.
In addition to this handy feature, the tool-bar offers an entire suite of useful tools for any web development project.
