Are you talking about the Master Password of the Firefox Password Manager?

https://support.mozilla.org/en-US/search?esab=a&w=1&q=Master%20Password

https://support.mozilla.org/kb/Forgot+my+master+password Resetting your master password will remove all of your saved usernames and passwords.

Why do you want to remove the software security device?

This device is usually about the Password Manager and Firefox asks for the master password when it needs to access the Password Manager.

You can delete the logins.json and key3.db files in the Firefox profile folder to remove all usernames and passwords stored in the Password Manager if you do not know the current master password.

You can use this button to go to the current Firefox profile folder:

• Help -> Troubleshooting Information -> Profile Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox

I never have used a Master Password! Today I keep getting asked for it! I don't want to use a Master Password, but the box is checked and I can't get it ti Uncheck.

Also today my page of bookmarks has been replaced by my old bookmarks of over a year ago! How can this happen, and how do I get my current bookmarks page back?

Have I been hacked or something?

Look on your desktop. Do you see a folder called; Old Firefox?

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Type about:profiles<enter> in the address bar. How many profiles are listed? How many should be there?

Kathy schrieb

I want to remove Software Security Device; they asking me for a master password which I don't remember

Try to rename/remove the secmode.db file in the Firefox profile folder if you still have this issue.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

• Help -> Troubleshooting Information -> Profile Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox