Browser compatibility for ReactJS web apps
Tags: react, testing, webdev, javascript
Published: 2022-01-30 16:25:14

User Experience is the key to customer delight and by ensuring a high-quality user experience through software development companies retain their customers. With the availability of a large number of devices and browsers, cross browser compatibility is essential for a seamless and consistent experience as the user switches between different devices and browsers. Cross Browser Testing thus becomes a non-negotiable and very essential part of the software development lifecycle. 

ReactJS is one of the most popularly used web frameworks among the developers as of 2021, hence understanding ReactJS browser compatibility is important to achieve the best results. As a [report by Statista](https://www.statista.com/statistics/1124699/worldwide-developer-survey-most-used-frameworks-web/) suggests, over 40% of the developers use ReactJS to develop web applications.


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/xa3vor2wxpar2vqharja.png)



## Cross Browser Compatibility with ReactJS

To have a sound knowledge of ReactJS cross-browser compatibility, it is essential to first understand how ReactJS works.


### How does ReactJS work?

ReactJS is an open-source JavaScript library that supports the front-end and the server using Document Object Model (DOM). It is used for UI development, wherein the user interface of the web application is developed as UI components that are aligned together for a complex comprehensive user experience. These UI components are isolated portions of the UI, based on the functions of the elements, which are further interconnected for an overall user experience. 

Unlike other JavaScript frameworks, ReactJS does not work with Real DOMs, rather it has a Virtual DOM, which is a lightweight representation of the Real DOMs in JavaScript. Here the DOM is represented through a Tree Data Structure with a node for each of the UI elements. This makes the updates faster, as the entire DOM is not changed but only the difference patch is updated by recognizing the affected nodes, which speeds up the loading. Moreover, ReactJS supports both client-side and server-side rendering, which further streamlines the user interface.


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/tydj87d4onakpm5wlk3o.png)



## React Cross Browser Compatibility

ReactJS offers code reusability, where a single piece of code for a UI component can be used across different platforms. This support for all the major browsers and platforms reflects React Cross Browser compatibility. Although a lot of the cross-browser compatibility is taken care of by the ReactJS itself, still Cross Browser Testing is important as some of the older versions of browsers have few limitations.

However, as React has individual UI components, [Cross Browser Testing](https://www.browserstack.com/cross-browser-testing) becomes easier and managing UX consistency across different browsers, platforms, and devices is simple. The testers can check for the [HTML5](https://www.browserstack.com/guide/html5-browser-compatible) and [CSS](https://www.browserstack.com/guide/css-for-browser-compatibility) codes of the elements to ensure cross-browser compatibility, in cases where certain features might cause inconsistencies for several browser versions.

Additionally, older versions can be supported by adding polyfills in a ReactJS web app to achieve cross browser compatibility. These polyfills are third-party JS files that work similarly to JS libraries. However, polyfills are also capable of providing new functionalities. For example, a polyfill can be used to support ES6-based features in browsers that fundamentally don’t.

When a ReactJS web app Airbnb was tested on different Real Devices using a [Real Device Cloud](https://www.browserstack.com/real-device-cloud)(desktops, mobiles, and tablets) across iOS and Android platforms, it was observed that the Airbnb app worked consistently on all the devices. It offered a seamless functionality providing the same user experience across different platforms and devices. Hence, it can be concluded that the Airbnb web app built using ReactJS is cross browser compatible, depicting the high browser compatibility offered by ReactJS framework.


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/f7e5ft7g9kzee4xfj1ji.png)


![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/kjy9muv7n551ah5qdlku.png)
  

ReactJS is one of the most popular web frameworks to build dynamic web applications. In a time when UX is pivotal and each of the web applications is accessed through multiple browsers and devices, it becomes essential to ensure a consistent user experience across browsers. Hence, React cross browser compatibility is significant during software development. By performing cross-browser tests on real browsers and devices, the tester could detect and highlight functionalities in the UX that are inconsistent with specific browser versions, which can later be fixed at the backend.