Thoughts on DNS-over-HTTPS

Updated November 30, 2020 with new information about DoH in Edge, ECH, and HTTPSSVC records, and January 25, 2021 with a few remarks about Edge’s implementation. Type https://example.com in your web browser’s address bar and hit enter. What happens? Before connecting to the example.com server, your browser must convert “example.com” to the network address atContinue reading “Thoughts on DNS-over-HTTPS”

Improving Privacy by Limiting Referrers

Updated July 31, 2020 to reflect changes planned to ship in Chrome 85 and Edge 86. As your browser navigates from page to page, servers are informed of the URL from where you’ve come from using the Referer HTTP header1; the document.referrer DOM property reveals the same information to JavaScript. Similarly, as the browser downloads theContinue reading “Improving Privacy by Limiting Referrers”

Same-Site Cookies By Default

The Chrome team is embarking on a clever and bold plan to change the recipe for cookies. It’s one of the most consequential changes to the web platform in almost a decade, but with any luck, users won’t notice anything has changed. But if you’re a web developer, you should start testing your sites andContinue reading “Same-Site Cookies By Default”

Web-to-App Communication: App Protocols

Note: This post is part of a series about Web-to-App Communication techniques.Last updated: June 4, 2025 Just over eight years ago, I wrote my last blog post about App Protocols, a class of URI schemes that typically1 open another program on your computer instead of returning data to the web browser. A valid scheme name isContinue reading “Web-to-App Communication: App Protocols”

Challenges with Federated Identity in modern browsers

Many websites offer a “Log in” capability where they don’t manage the user’s account; instead, they offer visitors the ability to “Login with <identity provider>.” When the user clicks the Login button on the original relying party (RP) website, they are navigated to a login page at the identity provider (IP) (e.g. login.microsoft.com) and then redirectedContinue reading “Challenges with Federated Identity in modern browsers”

Private Browsing Mode

Note: This blog post was originally written before the new Chromium-based Microsoft Edge was announced. As a consequence, it includes discussion of the behavior of the Legacy Microsoft Edge browser. The new Chromium-based Edge behaves largely the same way as Google Chrome. Last Update: 13 June 2025 InPrivate Mode was introduced in Internet Explorer 8Continue reading “Private Browsing Mode”

Cookie Controls, Revisited

Update: The October 2018 Cumulative Security Update (KB4462919) brings the RS5 Cookie Control changes described below to Windows 10 RS2, RS3, and RS4. Note: Most of the content about “Edge” in this post describes Edge Legacy– modern Edge is based on Chromium and behaves mostly like Chrome. See more discussion of 3P cookies in 2022’s NewContinue reading “Cookie Controls, Revisited”

Understanding the Limitations of HTTPS

A colleague recently forwarded me an article about the hazards of browsing on public WiFi with the question: “Doesn’t HTTPS fix this?” And the answer is, “Yes, generally.” As with most interesting questions, however, the complete answer is a bit more complicated. HTTPS is a powerful technology for helping secure the web; all websites should beContinue reading “Understanding the Limitations of HTTPS”

HTTPS Only Works If You Use It – Tipster Edition

It’s recently become fashionable for news organizations to build “anonymous tip” sites that permit members of the public to confidentially submit tips about stories of public interest. Unfortunately, would-be tipsters need to take great care when exploring such options, because many organizations aren’t using HTTPS properly to ensure that the user’s traffic to the newsContinue reading “HTTPS Only Works If You Use It – Tipster Edition”