Inkwell from InkPrint от Vu

Inkwell turns the entire web into your own handwriting. Sign in once with your InkPrint account and your custom font replaces the default typeface on every page you visit — articles, social feeds, docs, comments, everywhere text appears. The font follows you across tabs and browsing sessions automatically, with a built-in size slider in the popup so you can dial in how prominent it feels.

Privacy by design. Your handwriting font and session token stay in your browser's local storage. Nothing is uploaded to a third-party server; Inkwell only talks to your own InkPrint account to fetch your font, the same account you authenticated with.

To create your font, head to InkPrint (https://inkprintweb.vercel.app), sketch each letter once with a finger or trackpad or stylus, and let the app generate the OTF. Inkwell picks it up automatically the next time you open the popup.