Recently, I had to bring my new Windows 7 64-bit Home premium HP PC back to factory settings with a system recovery. All else on PC works just as before with excellent efficiency. I had to download the latest version of Mozilla Firefox and the install and import of saved bookmarks from my NAS external drive saved .json file went just as described. My Firefox 38.0.5 works well in all other aspects, but when I search in the Bookmarks sidebar field there is a huge lag after I type just one of the words in the title. My previous instal of FF 38.0.5 and other versions on the same PC were instantaneous in response and brought up suggested results faster than I could type the nest letter in the word. How can this be fixed as a complete uninstall and proper re-install of FF 38.0.5 did not make any difference.