Apologize for the lack of line breaks in the question.

1) Firefox crashed during normal use (surfing, playing media)

2) Somehow the application hung in a bad state, and I could not access task manager to kill process

3) Hard reboot

4) All passwords are gone

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options) key, and then starting Firefox. A small dialog should appear. Click Start In Safe Mode (not Refresh).

Is the problem still there?

While still in Safe Mode,

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP in front of the numbers/letters, click it to submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

Using your mouse, mark the most resent 7 - 10 crash reports, and copy them. Now go to the reply box below and paste them in.

Hello, thank you for the response!

1) The problem still exists in safe mode

2) There are no entries in about:crashes

Type about:profiles<enter> in the address bar. How many profiles are listed? How many should be listed?

These can't get your data back, but will help in the future.

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backups of files that you choose.

OPIE {web link} Import/Export extension preferences

about:profiles

"The address isn't valid" (although I'm still in safe mode...)

Yes, in the future I should probably store my passwords outside Firefox. "Fool me once" :)

Ahh, I see. https://support.mozilla.org/en-US/kb/update-firefox-latest-version 47

Then try about:profiles

Did you try another reboot?

Do you have an "Old Firefox Data" folder on the desktop in case you used the Refresh feature?

See also:

• http://kb.mozillazine.org/Recovering_a_missing_profile

Note that about:profiles is only available in Firefox 47 and not in the Firefox 43 version that shows in the System Details list.