Fast, Efficient, and Effective Cross-Browser Compatibility Testing

Have you ever encountered an issue with a website, called technical support, and they advise you to try that website in a different browser?

Ever wonder why?

Some websites don’t display correctly on different browsers. You may initially think that the website is ‘broken’, however, as soon as you open it in another browser - it works just fine. This is because each browser interprets the CSS code used in building the website differently and highlights the importance of cross-browser testing to ensure the compatibility of a website with different browsers.

Understanding Cross-Browser Testing

Cross-browser testing is the process of verifying whether the web application under test behaves as expected and is compatible with different browsers, operating systems, devices, and viewports. 

Its main objective is to confirm that a website functions, looks, and acts consistently or equivalently across a variety of browsers; this involves identifying: functional problems, inconsistent user experiences, and visual discrepancies.

The way web pages are rendered is one of the main issues of cross-browser compatibility. Discrepancies in font sizes, colors, spacing, and layout are examples of visual anomalies that can arise from browser-specific inconsistencies in how they interpret and apply CSS rules. The integrity of the website's design and user experience may be compromised by these discrepancies.

Compatibility issues may also arise from plugins like “Flash” and “Java”. As not all browsers support them and some have been completely disabled. As a result, certain website functions may stop working properly or become inaccessible to users on specific browsers.

The second most common issue is functionality, and verifying if the core features of the website are still functioning as expected across different browsers and devices. It is necessary to guarantee that the webpage or application is compatible with various browsers when viewed via:

• Different browsers, e.g: Google Chrome, Microsoft Edge, Mozilla Firefox, Apple Safari
• Different OS configurations, e.g: Windows, MacOS, Linux, iOS, Android
• Different devices, e.g: desktops, laptops, smartphones, and tablets
• Assistive technology i.e: website must be compatible with tools used by visually impaired users

The Importance of Cross-Browser Testing

A widespread misconception about cross-browser testing is that people assume it involves only testing on a small number of distinct browsers. But, contrary to popular belief, cross-browser testing is a much broader term that takes into account the number of versions of those browsers, operating systems, devices, and more. A different combination of them can provide different experiences. 

For example, many businesses test their websites exclusively on Google Chrome, but as of April 2023, Chrome only held 63% of the browser market share. This means that we run the risk of failing to evaluate the online experience for over 35% of users. Without cross-browser testing, we are unable to determine if the websites work consistently across a wide range of browsers and devices that users may use to access them. This is before even taking into account different devices such as mobiles and tablets and different operating systems.

How to Implement Cross-Browser Testing 

What to test

Selecting a browser to test with can be a difficult process for any tester, given the wide range of browsers, versions, and platforms. However, the client and the business research team have a major role in deciding which of the most widely used browsers and devices should be tested by gathering usage and traffic statistics. 

Older versions of the selected browsers should not be excluded, given that a significant portion of the users might still use them. Specialist situations have to be identified as well. One example is with the rise of the new generation of flip phones, websites now have to be compatible with a whole new type of device, especially if that device is used by a significant portion of a business's user base.

When to test

In order to guarantee that new features operate as intended, and to avoid breaking previously working elements due to new code additions (regressions), cross-browser testing, alongside regression testing, should be performed continuously throughout the software development lifecycle.  To maintain high-quality standards and reduce time-to-market, it is suggested to implement cross-browser and regression testing activities in continuous integration (CI) and continuous delivery (CD) pipelines.

If cross-browser testing is put off until the very end of the project, it becomes much more difficult and expensive to fix any issues that are found, as opposed to fixing them incrementally as the project progresses.

What Kind Of Test Types Are There?

With respect to conducting an efficient and effective cross-browser test, it is important to consider the following test types:

UI/UX Testing

The main focus of this type of testing is the visual appearance of a website across different browsers. It may include checking if fonts, colors, and layouts are shown consistently, as well as, ensuring that there are no glitches, broken images, or margin misalignments. 

Functional testing

This type of testing verifies that all interactive features and functionalities work as intended according to the specified requirements across different browsers. It may include checking if all buttons are responsive, navigation menus working correctly, account creation or password reset, error messages, links, dialogues, and any other functions vital to the performance of the website and business.

Performance testing

This type of testing evaluates how fast a website loads and how responsive it is on different browsers and devices. The website’s load time on Chrome might differ from Safari. Responsiveness on Firefox may be different from Edge. The application might cause a crash on mobile devices, while on desktop, it behaves as expected. Everything should be accounted for.

Browser version testing 

To support the users who still have not updated their browser version, different versions of a particular browser must be tested. An example would be: testing a feature on an older version of Chrome (115) or simply comparing older with newer versions of the browser.

Accessibility testing 

This type of testing makes sure that a website across different browsers conforms with accessibility guidelines like WCAG and/or ARIA attributes and can be used by individuals with impairments and disabilities.

Managing The Flow Of The Testing Process

The following steps represent the primary flow of the testing process, albeit they may differ depending on the project:

1. Determining which browsers, browser versions, and operating systems should be included in the testing scope. 
2. Identifying test cases that cover the features and key functionalities that need to be tested across various browsers. 
3. Setting up virtual machines and physical devices to cover various browsers and operating system combinations. Installing different browser versions and ensuring they are up to date also takes place at this stage.
4. Executing test cases across the selected browsers, operating systems, and devices, while ensuring that every browser works with the application consistently, displaying content appropriately as per the specified requirements.
5. Once testing is complete, document any issues or discrepancies that were discovered. Analyze and debug underlying causes of these issues, and work with developers to find potential solutions.
6. Once issues have been fixed, retesting them to ensure they are resolved across all browsers and platforms. 

Manual vs. Automated Cross-Browser Testing

The conventional approach to cross-browser testing is manual testing. 

While it was pretty convenient to install every browser on every system when there were few browsers and the need for cross-browser testing was low, the number of operating systems and browsers has increased over time, making it difficult to manually cover such a wide combination. Therefore, for the application to function flawlessly across a range of platform and device combinations, automated cross-browser testing is now recommended, especially for more repetitive tasks. Manual testing still has its advantages, however, due to its ability to find specific detailed issues.

Whilst being the time-saving testing method, test automation tools also let you test an application on multiple different browsers and browser versions, even without having to install them. 

Automation tools also help create and execute repetitive test cases to improve test consistency, efficiency, and accuracy. A good automation tool should:

• Have functional testing and UI testing built-in
• Support a wide range of browsers and their versions
• Support a wide range of screen resolutions
• Support both web and mobile applications

Deciding whether your team should choose manual or automated testing depends on the specific testing project. A good rule of thumb is, that you should only automate repetitive tests, and manually perform ad hoc, exploratory and usability tests.

Cross-Browser Testing Disadvantages

While Cross-Browser testing may seem straightforward, there are potential drawbacks:

Numerous Browser and OS combinations

Among the most frequent challenges encountered by testers, the ever-increasing number of combinations leads to new bugs to find and increased workloads.

Cross-Browser testing can be time-consuming

To provide sufficient coverage, a significant amount of browser combinations must be tested. As a result, it becomes time-consuming.

Continuous updates

Browser vendors continuously release updated versions. This requires keeping the browser versions up-to-date.

Limited access to physical devices

If mobile testing coverage is needed, access to all of the mobile devices can be limited, unless using an outsourced partner.

Automating cross-browser tests are not that easy

To ensure optimal performance, automated cross-browser testing requires careful planning and appropriate tools, which include building automation scripts. These activities take time and effort.

In Conclusion

Cross-browser testing contributes to making a positive first impression on users by providing them with a consistent and unified experience, regardless of their selected browser or operating system. 

The process does pose some challenges, as well as time and resources. Nevertheless, these disadvantages are greatly outweighed by its benefits, such as ensuring the functionality of web features crucial to business functions (e.g. “Checkout” and “Contact Us” buttons). As well as, improved user experiences and visibility, which inevitably leads to reaching larger audiences.