At Mozilla a fundamental part of our beliefs is that all websites should work equally well across all browsers and all devices. The Internet should just work everywhere, flawlessly, with no questions asked. We’re therefore really happy that, as of this week, the BrowserStack team is launching a mobile test capability for Firefox browser products and a unique offering – one year of free testing on Firefox mobile browsers on BrowserStack’s Real Device Cloud. In addition, developers can test Firefox browsers on different desktop operating systems for free for 30 days.

We know that today the majority of web content consumption and activity is on mobile. That’s what makes BrowserStack’s new Firefox test capability so important for web developers trying to build web compatible mobile sites. And helping developers be more successful with their sites is great for users too, and for Mozilla.

All of us have experienced badly broken websites. Pull-down menus that don’t work, overlapping text or borders, submit buttons that don’t submit, or forms that are invisible all are common symptoms of incompatibly. What do you do when you hit a broken website? You usually leave it for another website, and if the problem is frustrating enough you might even try a different browser.

On mobile these problems of web compatibility are even more challenging because of the multitude of devices we all use. Developers building sites for the mobile web must make sure their code works across hundreds of types of devices with different screen sizes, display densities, and many more variables.

We know there are many reasons why the web breaks. There are numerous standards, implemented differently by the browser makers. For users, telling whether a site is broken or is simply a function of bad user experience design on the limited screen real estate of a phone is nearly impossible.

Today, even ensuring mobile website compatibility and equal functionality across the major desktop browser platforms – Firefox, Chrome, Windows – and major mobile operating systems – iOS, Android– requires a lot of effort. Many hours more effort. We recognize that to build mobile sites that just work on all browsers, developers need a solid mobile test environment.

By partnering with BrowserStack, we at Mozilla are aiming to provide developers with an easy, free way to test their content everywhere, especially on Firefox, so that they can deliver quality experiences on any device and browser combination.

Developers that use BrowserStack to test their site code for web compatibility include many well known web properties such as Microsoft, AirBnB, and MasterCard. Mozilla will be using BrowserStack as part of our ongoing efforts to grow usage of Firefox mobile both by using it to test our own properties and as part of our evangelism efforts to identify and help fix incompatible sites out on the web. BrowserStack’s compatibility testing tools will make it much easier for our internal engineering teams to identify compatibility problems in the wild and more quickly fix them.

This is only the first step in our partnership. In Q2 we will announce testing on Firefox for iOS. We will continue to work closely with BrowserStack to get the word out to the developer community. Our teams at Mozilla Developer Network (MDN) will provide additional documentation on how to use BrowserStack to test sites for compatibility on Firefox. And on our Mozilla Developer Roadshow (hopefully coming to a city near you soon), we will have our compatibility experts explaining how you can benefit from testing Firefox on Mobile with BrowserStack. The best part about this is truly everyone benefits. Developers can more quickly find and fix compatibility issues for Firefox on mobile devices. Users on Firefox mobile will get a better web experience as more and more developers comprehensively test their site code.