Briefings

Field notes on user agents, fingerprinting, and cross-browser testing.

• June 14, 2026 A Practical Workflow for Testing Responsive Sites With Different User Agents

  How to use a handful of user agent strings, alongside real device testing, to catch browser-specific bugs before launch.

• June 1, 2026 Common Mistakes That Make a Fake User Agent Obvious

  The mismatches — stale versions, impossible OS/browser pairs, inconsistent headers — that give away a spoofed user agent immediately.

• May 19, 2026 Why Changing Your User Agent Isn't the Same as Changing Your Fingerprint

  User agent strings are one signal among dozens. Here is what else sites look at, and why swapping one string rarely changes much on its own.

• May 6, 2026 Reading a User Agent String Part by Part (Chrome, Firefox, Safari Compared)

  A field guide to what each token in a user agent string actually means, with Chrome, Firefox, and Safari broken down side by side.