The master password is requested at every startup of Firefox since I updated the Windows 10 system with the updates of May 2019. This happens with the same behaviour exactly on both my two PCs. I updated the Windows 10 system in both of them and then the issue appeared in both of them. I've tried all the following issues: - I deleted all the profile settings from the AppData folder and I started Firefox with a new blank profile: the issue disappears, but after I set a new master password, after some time of browsing, the master password is requested at a random moment (no apperent cause for that). From that moment, the master password is requested at every startup of Firefox. - I'm NOT logged into Sync - The issue happens even starting Firefox with a blank page - my security.enterprise_roots.enabled setting is set to FALSE - I have NO antivirus installed in the system, neither Avast, nor Kaspersky Thank you.