Loading regular pages like HomeDepot or Wellsfargo are very slow. Can take 30 sec. Videos from CNN or Youtube can take 1 min top load if at all. I have gigabit internet and pages load withing 2 sec on Microsoft Edge. I have tried complete removal and reinstallation of Firefox. I have default theme and no extensions installed. I have tried turning off Norton 360 firewall and antivirus, starting Firefox in safe mode, starting Windows 10 in safemode. Nothing helps. Have not only scanned computer with Norton but also with Malwarebytes and found no adware/ viruses. HTML5 seems to be working fine according to a diagnostic page I visited. Firefox works great on my laptop from same internet connection. Have 40 gigabytes free space on disk drive. Please help