I have been using 1Password 7 to manage my login credentials. It includes a Firefox extension to fill in account names and passwords in login alerts and pages. Firefox 147.0.1 (macOS aarch64) in January 2026 has broken 1Password 7's ability to fill in account names and passwords. To reproduce: 1. Install 1Password 7 Version 7.9.11 (70911000) and its extension version 4.7.5.90 in Firefox 147.0.1 on macOS. 2. Visit a URL for which 1Password 7 has login credentials. 3. Click on the toolbar icon for 1Password 7. A 1Password 7 dialogue box pops down from the icon, containing the username and password for that URL. 4. Click the Autofill button in that dialogue box. Observed behaviour: 1. Username and Password fields remain blank. Expected behaviour: 1. Username and Password from 1Password 7 appear in the Username and Password fields. For approximately the last three months, there was a partial failure similar to this. 1. 1Password 7 popdown dialogue moves from the toolbar icon to the Firefox tab for that URL. 2. Username and Password fields remain blank. 3. Workaround: click in the username field, then tab 2-4 times to further UI objects in the login credentials form. Then click the 1Password toolbar icon, then click the Autofill button in the popdown dialogue. Then, the Username and Password from 1Password 7 appear in the Username and Password fields. The expected behaviour occurs for the same URLs in Safari. Thus I suspect that Firefox has somehow changed its behaviour in the last few months to cause this regression. I have not changed the 1Password software versions in this time, because I am intentionally using a previous version of 1Password. I am looking for a fix or workaround which works with my current 1Password software version. I am not interested in a solution which requires me to upgrade to the current version of 1Password. (The current version of 1Password imposes a feature which I am resisting.) I realise that this reduces the chance that I can persuade the Firefox team to find and correct this regression.