What is Microsoft Edge’s Super Duper Secure Mode?How to enable it

Rate this post

Microsoft is experimenting with new features to enhance security while browsing the Internet through Edge. The browser already offers three levels of privacy protection, including Basic, Balanced and Strict. But now Microsoft Edge is testing a new feature called Super Duper Secure mode for added security. In this article you will learn everything about this feature. This includes what Edge’s Super Duper Secure mode is, its strengths and weaknesses, and how you can test future features right away.

Use Super Duper Secure Mode with Microsoft Edge (2021)

Edge’s Super Duper Secure mode is now available behind the feature flags for Canary, Dev, and Beta channels. If you’re using Edge on any of these channels, here’s how to try Edge before the general release.

What is Microsoft Edge’s Super Duper Secure Mode?

Super Duper Secure Mode (SDSM) is an experimental feature of Edge to improve browser security. The name of this feature is now a bit … edgy, but Microsoft says it may be renamed before it ships to a stable version. And of course, this is an experimental feature, so SDSM may not reach a stable Edge build.

So what does Super Duper Secure mode do? Before that, it’s important to understand how modern JavaScript engines work. To ensure performance The JS engine uses what is called Just-In-Time (JIT) compile. With JIT, compilation is done at run time. This approach has advantages such as optimization and faster overall performance.

However, there are security issues with the JIT. As Microsoft points out, almost 45% of Common Vulnerabilities and Exposures (CVEs) published for the V8 JavaScript engine are JIT related. Another Mozilla analysis quoted by Microsoft reveals that the majority of vulnerabilities are JIT-related, as shown in the graph below.

Vulnerability by type
Image: Mozilla

To improve the security of the Microsoft Edge browser, what Super Duper Secure mode does is disable the JIT (TurboFan / Sparkplug). Instead, it enables Control-flow Enforcement Technology (CET), Intel’s hardware-based exploit mitigation system, to protect your PC from common malware. Microsoft hopes to add Arbitrary Code Guard (ACG) and Control Flow Guard (CFG) protection in the near future. The company also plans to introduce this feature to Android and Mac versions of Edge.

If you want to know the strengths and weaknesses of this feature, check out the next section.

Benefits of Microsoft Edge Super Duper Secure Mode

The main advantage of using this mode is increased security. According to Microsoft Enabling this feature will disable the JIT and remove half of the V8 bugs... In addition, the actual discovery of critical JIT-related vulnerabilities reduces the demand for frequent security and emergency patches.

Also, JIT does not work well with CET, ACG, and other mitigation tools, so disabling JIT gives users a secure experience while browsing the web. “This reduction in attack surface kills half of the bugs found on the exploit, making all the remaining bugs more difficult to exploit. In other words, it reduces the cost of the user, but the cost of the attacker. Will increase. “ Microsoft says.

Disadvantages of Microsoft Edge Super Duper Secure Mode

The most obvious disadvantage of this approach is performance, as the JIT is not working. However, according to Microsoft lab tests, most users may not notice the difference. Microsoft has run tests in various categories such as power, boot, memory, and page loading.


When super secure mode was enabled, internal testing conducted by Microsoft showed little change in performance. The company noticed an average 15% improvement and an 11% reduction in electricity. Memory usage, on the other hand, had a 2.3% regression in the adversely affected test, but a value of 4.6% in the positive test. Page load times returned the most at 17%, with an improvement of 9.5%. Disabling JIT improved startup time by 8.9%. This is a small plus that comes from this change.


The impact on overall performance also depends on usage patterns. To address this, Microsoft plans to give users more control and allow them to configure features based on their needs.

Another drawback is Edge SDSM does not yet support WebAssembly.. However, the company has promised to add support for WebAssembly in the coming months.

Enable Super Duper Secure Mode on Microsoft Edge

Now that we know what Edge’s future security mode is, we’ll show you how to try it now. Follow the steps below to enable the SDSM edge flag.

1. Open the Edge Flags page (go to this address – edge: // flags) and search for “Super Duper Secure Mode”. Alternatively, you can access the flag by pasting the following address into Edge:


Super Duper Secure Mode Flag

2. From the drop-down menu next to the flag Select “Enabled” Restart the Edge browser. This will disable JIT in Edge and allow you to enjoy a safer browsing experience.

Enable Super Duper Secure Mode Edge

Browse securely in Edge’s Super Duper secure mode

So that’s all you need to know before trying out the new Super Duper Secure Mode in Microsoft Edge. The name may be different at startup, the functionality may remain the same, but with a slight improvement. Would you consider using this feature to enhance your online security? Share your thoughts in the comments section below. Also, for more Edge-related features, see our article on Edge’s Best Tips and Tips.