Open and Fill is adding random data after the URL

Hello jimgarrison! 👋

Thank you for the question. When you click “Open & Fill” from inside of an item in the 1Password desktop app, a string representing that item is appended to the URL sent to the browser. Think of the URL like a secret handshake between the desktop app and the browser extension to help the extension automatically fill your login credentials into the webpage when it opens.

The 404 error that you mentioned is likely coming from the website's security policies, they may have set that they only accept certain URL parameters are legitimate. Unfortunately this isn't something that 1Password can control from our end.

To workaround the issue on that particular webpage, I would recommend opening the site in your browser first and then filling your login using 1Password in the browser's inline filling menu rather than opening the website from inside of the desktop app.

Please let me know if you have any questions.

-Dave