More specifically open https://mynoise.net/NoiseMachines/whiteNoiseGenerator.php and press ‘b’ for brown noise. Use j/k for volume.
I use this all the time, long before the article. White nose improves focus in everyone, not just ADHD folks.
This workflow is part of my standard work. If I have a document to read, a code review, or something that’s not mechanical coding (which I use music for), brown noise helps increase focus.