Passwords and information for them and sites all gone?!

Not a direct fix, but I use KeePassXC for all my passwords and raindrop.io (free version) for all my bookmarks. These are both cross-platform and cross-browser. This makes them both available everywhere. My passwords are stored and backed up (by me) wherever I want them. I can even store them in the cloud (Dropbox, etc.) and access them from my phone and from my notebooks. This avoids problems such as the one you are experiencing and gives me enhanced functionality.