In contrast to establishing webpage based on responsive web design, checking whether our work turn out to be correct is a piece of cake. Especially, while using Firefox, which is definitely one of the most friendly browsers when it comes to rwd tests.
One of the easiest and quickest way of checking the responsiveness of the website, which we are browsing at the moment is using a special Firefox hot key. Just click Ctrl + Shift + M and you will see your website configured into one of the seven (excluding website’s own size) common resolutions:
THE SIMPLEST WAY
Another very simple (for some definitely TOO simple) way of checking the responsiveness of our website. Click F12, Tools → Change size, where you can also choose from different resolutions you want to verify. You may also go to pop-up menu and choose Check the element and clicking adequate icon on the right side of the menu.
These are the simplest and the easiest way of checking the responsiveness of your Firefox website. It is worth to pay attention to the details and be careful about adjusting your content to mobile devices.