Paper Plane privacy

Paper Plane doesn’t collect, store or send any personal data, apart from notes by plane, which are stored sealed (see the notes line below).

• It reads nothing from the pages you visit except where things are on screen: the window size and whether something is pinned along the bottom edge, so it can rest there. It never reads what any text says, what an image shows, or anything you type. Typing is noticed only as “a key was pressed in a field”, so the plane can keep still.
• Your settings (on/off, sites you’ve turned it off for, mood, size, sound, snooze) are kept by Chrome’s own extension storage, synced only through your Chrome profile if you use Chrome sync. The plane’s last position, and what it remembers about your play (how many throws, your longest throws overall and per site name, which tips you’ve seen, how often you’ve hidden it on a site, when you last saw it), and the plane’s diary (a line a day for the last 60 days: throws, loops, distance, finds, planes folded), how far it has flown in all, and where along the way it found things, are kept locally on your computer, in Chrome’s extension storage. They’re never synced or sent anywhere.
• Notes you leave for yourself (in Tools on the plane’s page, or from the page’s or the plane’s right-click menu), the timer, and the scroll check-in’s count of how long you’ve scrolled on the sites you listed are kept locally on your computer, in Chrome’s extension storage. Notes are matched to a site by its name (like github.com) on your computer; nothing about them is synced or sent. The check-in settings (on or off, your list of sites, the minutes) sync with your other settings.
• The path of your longest throw (where the plane was on screen) is kept locally too. It only leaves your computer if you press “Share your longest throw”, and then only inside the link you share, after the #.
• Notes by plane (on the website) are encrypted in your browser and kept for 7 days, then deleted (within about a day), padded so even their length is hidden. The key is only in the link you share, after the #, which browsers don’t send to any server, so the site can’t read them. Sealed copies may also stay in a cache for up to a day, and nobody can open them. If a note can’t be stored, the whole note goes in the link instead, as before. Notes you send are also kept in your browser for 7 days, so a reply can show your own words, along with the name you last signed; none of it leaves your browser.
• The extension has no analytics and sends nothing to any server.
• The website counts visits anonymously, to see which pages people use: no cookies, nothing that identifies you, and nothing that follows you to other sites.
• There are no accounts and no ads, and nothing about you is sold.

The “read and change all your data on all websites” permission is what lets the plane appear on any site you visit, including ones with strict security settings. It’s used only to draw the plane.