You can check the home page setting:

• Tools > Options > General > Startup: Home page

Firefox supports multiple home pages separated by '|' (pipe) symbols.

• https://support.mozilla.org/kb/How+to+set+the+home+page

Your System Details list shows that you have a user.js file in the profile folder to initialize prefs each time Firefox starts.

The user.js file is only present if you or other software has created this file and normally it wouldn't be there. You can check its content with a plain text editor (right-click: Open with) if you didn't create this file yourself.

The user.js file is read each time Firefox is started and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.

See also:

• http://kb.mozillazine.org/Preferences_not_saved

You have several extensions that I wouldn't let near my computer. I suggest that you Google and use the Search Box above to review them, one by one, for information, and removal advice where appropriate; and consider what you actually use them for.

Feedback? A response could help the contributor/users and other users.