Not locking 1Password8 on browser close

Fedup thank you for providing those screenshots of your settings in both the desktop app and the browser extension! I took a look at them and I believe I've spotted the issue. In the browser extension's settings, you have the "Integrate with 1Password app" setting toggled to the off position (this can be found at the bottom of the "General" section).

If you toggle the setting back to the on position, the browser extension should be able to successfully lock / unlock in tandem with the desktop app. Let me know if that gets things working for you!