Microsoft reveals how it is trying to improve performance in its Edge browser with WebUI 2.0

Microsoft continually updates its Edge web browser every few weeks with new features, bug fixes, and security upgrades. However, the company says it has also been quietly trying to increase the overall performance of Edge in the last few stable versions.

In a blog post today, Microsoft revealed that with the release of Edge 122 in late February it has boosted the response time for the Browser Essentials UI by 42 percent for Edge users. That performance increased by an even higher 76 percent if a user has a PC that does not have an SSD for storage and it has less than 8GB of RAM.

Microsoft also revealed that the Favorites feature in Edge 124 in mid-April also got a performance increase. It says the Favorite UI should be 40 percent faster for responses than before the update. The performance boost is available if Favorites is expanded or collapsed.

Microsoft says these changes were due to data it has been collecting from Edge users in terms of its UI response. It found there were two areas where it could make changes to increase the UI speed. One was that the UI code was not modular enough, with Microsoft stating that some parts of the code were "sharing things unnecessarily" which resulted in slowdowns.

The other issue was Edge was using JavaScript to handle client-side rendering of the UI. Microsoft stated:

Why are we sharing this ancient news? After all, a lot of web pages have been rendering on the client-side for years. Well, it turns out that JavaScript must be downloaded, then run through a JIT compiler (even if you don’t use it), and then executed, and all this must be done before any of the JavaScript can start rendering the UI. This introduces a lot of delay before users can see the UI, especially on low-end devices.

The Edge team decided to work on a new project it called WebUI 2.0. The blog stated:

In this project, we built an entirely new markup-first architecture that minimizes the size of our bundles of code, and the amount of JavaScript code that runs during the initialization path of the UI. This new internal UI architecture is more modular, and we now rely on a repository of web components that are tuned for performance on modern web engines. 

Microsoft put WebUI 2.0 to work with the Browser Essentials UI in Edge, and saw a big boost in speed. The plan is to upgrade other UI features in Edge to the new WebUI 2.0, so we should see even more increases in speed in the coming months.