Detecting When the User is Offline

Can you hear me now? In the web platform, simple tasks are often anything but. Properly detecting whether the user is online/offline has been one of the “Surprisingly hard problems in computing” since, well, forever. Web developers often ask one question (“Is this browser online?”) but when you dig into it, they’re really trying toContinue reading “Detecting When the User is Offline”

New TLDs: Not Bad, Actually

The Top Level Domain (TLD) is the final label in a fully-qualified domain name: The most common TLD you’ll see is com, but you may be surprised to learn that there are 1479 registered TLDs today. This list can be subdivided into categories: Some TLD owners will rent domain names under the TLD to anyContinue reading “New TLDs: Not Bad, Actually”

(The Futility of) Keeping Secrets from Yourself

Many interesting problems in software design boil down to “I need my client application to know a secret, but I don’t want the user of that application (or malware) to be able to learn that secret.“ Some examples include: …and likely others. In general, if your design relies on having a client protect a secretContinue reading “(The Futility of) Keeping Secrets from Yourself”

Auth Flows in a Partitioned World

Back in 2019, I explained how browsers’ cookie controls and privacy features present challenges for common longstanding patterns for authentication flows. Such flows often rely upon an Identity Provider (IdP) having access to its own cookies both on top-level pages served by the IdP and when the IdP receives a HTTP request from an XmlHttpRequest/fetchContinue reading “Auth Flows in a Partitioned World”