Password Filler

About

Password Filler automatically fills HTTP Basic Auth login dialogs using credentials stored in your 1Password vault — no copy-pasting required.

THIS EXTENSION WORKS WITH THE PASSWORD FILLER MACOS DESKTOP APPLICATION. It is a thin proxy that has no functionality on its own. macOS only.

Get the Mac app: https://github.com/andreasisaak/password-filler/releases/latest

HOW IT WORKS
When a website returns 401 + WWW-Authenticate: Basic, the extension asks the local Mac app for matching credentials and fills the dialog before the browser shows it. If the Mac app isn't running, the native browser dialog appears as usual.

REQUIREMENTS
- macOS 14 (Sonoma) or newer
- 1Password 8 desktop app, signed in, with "Integrate with 1Password CLI" enabled
- Password Filler Mac app installed (free, open source)

PERMISSIONS EXPLAINED
- webRequest + webRequestAuthProvider: detect 401 challenges and supply credentials to the auth-provider API so the dialog fills silently
- nativeMessaging: talk to the local Mac app over Chrome's Native Messaging channel — never to any remote server
- alarms: keep the service worker alive between auth challenges so the Native Messaging port stays connected
- host permissions on all URLs: HTTP Basic Auth can occur on any URL — the extension reads ONLY the hostname of 401 responses, never page content, cookies, headers, or form data

PRIVACY
All credential lookups happen entirely on your device. No data is sent to any external server. Passwords are never written to disk by the extension; they live in your local 1Password vault and are encrypted at rest by the Mac app.