OK, it could've been that I opened it for the first time in a year, but still, there are no addons, no history, no bookmarks, nothing - a new Firefox or Chrome

OK, it could've been that I opened it for the first time in a year, but still, there are no addons, no history, no bookmarks, nothing - a new Firefox or Chrome installation never behaved like this. It's on an SSD, too, so what could be the issue then?