How I built a browser watermark library that survives DevTools

Identifying the leaker after a screenshot escapes, when the obvious tricks no longer work. The problem Last year, I watched a customer of ours forward a screenshot of an internal dashboard to a vendor. The screenshot showed financial figures that should have stayed inside the company. Nobody could prove who took it. If every pixel of that screen had carried that user's email or ID in faint diagonal text, we would have known the answer in five seconds. That is the whole idea behind a watermark. I