This is not a problem related to firefox. this is your system property. You can see in the screenshot that your notification box is on the right of the taskbar. So changing its position according to your preference will help you. There is no way to move the Notifications in Windows 10, '''the only option would be to move your Taskbar to another edge of your screen, that would move the Notifications location ''' for reference [https://support.microsoft.com/en-us/windows/customize-the-taskbar-notification-area-e159e8d2-9ac5-b2bd-61c5-bb63c1d437c3 https://support.microsoft.com/en-us/windows/customize-the-taskbar-notification-area-e159e8d2-9ac5-b2bd-61c5-bb63c1d437c3]