I'm running Firefox ESR 52.1.2 (32-bit) on my fully patched Vista machine. This morning FF behaved nicely when opening my Home Page and my regular haunts, favourites etc, but type a question in the address bar and it will search endlessly. e.g "Is Google real?" "What is the UK Inflation rate?" "What to do with Basil Leaves?" Just hitting the "Red X" to slam the door shut, so to speak and re-start FF, I then "restore Previous session" and the tabs then find the required info! FF did apply some updates yesterday, ...if that helps!