I use LastPass to manage my passwords. It has worked well with Firefox on a Dell running Windows 10 for several years. For the past week or two the LastPass icon is black meaning not logged in. I enter my email and masterpassword and I see a vault with a spinning wheel for about 30 seconds and then the icon goes black again. No error message. If I click on the icon it shows I need to log in. I've tried reinstalling the extension but the problem persists. LastPass works fine for me on the same computer using Chrome for Windows. It also works with no issues when using Safari and Firefox on my Apple Macbook.