To add a page to your desktop, go to Control panel, Display, Desktop, and choose "Customize Desktop". On the "Web" tab click "New" and add the location of your to-do list HTML file, as shown.

Now [Andy Green] has extended the possibilities with affordable silicon, by producing a proof-of-concept HTML + CSS renderer over h2 on ESP32 for libwebsockets. Surf the web on a microcontroller ...