Seriously problematic hotel logon.
Logging in at a hotel, I tried to use Google Chrome. Hotels redirect, and can disrupt browser history. Chrome came on the computer, and usually can keep those disruptions out of my actual work area. But this?!?!
Firefox is my default browser. Despite having Chrome open, it opened Firefox automatically. (By "it", I mean a Dell PC.) Everything hung! By the time I was logged on, my previous work session, 30 or so tabs in 2 windows, was gone. Also gone: Various add ons like Ad Blocker & NoScript. All the add-ons in fact - every last one. I keep a google search slot open on top. (Is that the tookbar?) Anyhow even that disappeared. No telling what else will turn up missing and changed when I dig around in the settings.
Were you using the hotel's computer or your own? It sounds like the browser did a refresh.
Also gone: All the add-ons
Look on your desktop. Do you see a folder called; Old Firefox? Look inside. Look for the folder with the latest creation date.