I use FF 38.5.1esr because it's the most recent version of FF with which the add-on "Duplicate 2 Window" works (it causes Ctl-N to open the new window with the current URL instead of the home page). Also, I've always had the preference for link-clicks to open new windows, rather than new tabs or moving to the new page in the same window: "Open new windows in a new tab instead" Option in the General tab has been left Unchecked. 3 days ago my FF crashed instantly on startup: Just the crash reporter displayed but it was unable to send anything. Neither Refresh nor Safe Mode worked. I uninstalled FF and ran my previously downloaded clean installer. FF started up successfully. History, bookmarks, add-ons, etc. all in tact. Even Options setting were unchanged. Including "Open new windows in a new tab instead" being left Unchecked. NOW, however, every time I click on a link - in Google, say - the new URL displays in the same tab of the same window. I even checked browser.link.open_newwindow in about:config and it's still set to 2 (so is browser.link.open_newwindow.restriction). Any insights or suggestions would sure be appreciated! Thanks, Lrand0