Hi, please try : https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save but before doing so : *https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer Please let us know if this solved your issue or if need further assistance.

See also: *http://kb.mozillazine.org/browser.link.open_newwindow *1: current tab; 2:new window; 3:new tab; For links opened via JavaScript you can look at this pref: *http://kb.mozillazine.org/browser.link.open_newwindow.restriction Note that internal pages like Options/Preferences and Add-ons will still open in a new tab.

I don't think it is a configuration problem; it's a choice you make in preferences. I had windows, private or public, but decided to use tabs. I don't like tabs, so I went back and removed the choices for tabs. I marked windows. But the change is not working.

Hi, so you have 4 untried options please report back after you have tried them. 1) Please respond to my 1st post as to doing what the URL states fixes the issue....... *https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save 2) Or can try a Refresh : https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings 3) or Uninstall and delete all Firefox/Mozilla folders in all your folders but save bookmarks and Profile (even though Profile is possibly causing the issue). *https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data * https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer Reinstall with Current Release Firefox 59.0.2 with a Full Version Installer *https://www.mozilla.org/firefox/all/ 4) Or it is your Profile : Make a new one and test ...: *https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles If is your Profile : *https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile *http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox Please let us know if this solved your issue or if need further assistance.