I'm on a Mac, High Sierra. With each new version of Firefox Quantum performance gets worse and worse. It's so bad I am using Chrome to type this complaint. Firefox allows me to type 2 letters before it waits for a minute to gather itself so I can type another 2 letters. Try doing a search that way - It takes all night to type a short query. And I lost the Add-on bar at the bottom. From the numbers of complaints, Mozilla doesn't seem to be in any frame of mind to solve any problems, it's their way or the highway. I'm off to Chrome. I'm done searching a user forum for answers, let's hear from Mozilla. Why should I have to search and try tips (ad nauseam and most don't work) from forum participants. This is no way to run a business.