Notes from building READR — engineering write-ups, debugging stories, and the thinking behind a private reader-mode extension.
10 Oct 2026 · Engineering
Why my Chrome extension's PDF export was blank on Wikipedia
html2canvas returned blank PDFs on Wikipedia — and the real cause was something I'd never have guessed from the symptom. A debugging post-mortem on CSP, empty canvases, and the jsPDF fix that made it work everywhere.
html2canvas · CSP · jsPDF