Back up both keyfiles then try renaming Key3 to key4 and see if it "moves" them then.

Hi,

I wondered if renaming might work, don't why I didn't think of that before. Thank you for your reply. I'll rename the file.

You need to remove key4.db (SQLite) if you only have key3.db (DBM) to make Firefox fallback to using the key3.db file as key file.

Hi Thank you for your reply. Ok, I'll try deleting key4.db, as renaming key3.db didn't work.

Kind regards, Matt

Hi again,

Thanks very much for the responses, unfortunately removing key4.db also didn't work. (I made sure that the only relevent files in the new profile were key3.db and logins.json). When I look for my logins in preferences > security > saved logins I am not prompted for a master password and my logins aren't there. Do you know if there is anything else wrong?

Kind regards, Matt

Are you sure that you have a matching logins.json and key3.db file ?

You did copy both files (logins.json and key3.db) another time with Firefox closed ?

Are there error messages in the Browser Console about the login manager ?

• "3-bar" menu button or Tools -> Web Developer
• https://developer.mozilla.org/en-US/Tools/Browser_Console

Does Firefox rename logins.json to logins.json.corrupt ?

Does about:protections show any logins detected ?

Yes they definitely match because when I use them in Firefox 49 they work

Firefox was closed when I copied the files from my old profile

I can't see a logins.json corrupt in the profile

the browser console shows the following error messages, I don't know if they're relevent: Error: Can't find profile directory. 8 XULStore.jsm:66:15

   load resource://gre/modules/XULStore.jsm:66
   XULStore resource://gre/modules/XULStore.jsm:24

NS_ERROR_FAILURE: Couldn't decrypt string 160 crypto-SDR.js:200

   decrypt resource://gre/modules/crypto-SDR.js:200
   getAllLoginsAsync resource://gre/modules/storage-json.js:383
   InterpretGeneratorResume self-hosted:1151
   AsyncFunctionNext self-hosted:693

Yes, I can't see the logins on the logins screen when I click on the view logins button next to the information in about:protections but about:protections, shows 'your passwords are being stored securely' which isn't displayed before I copy the files in. The message appears after I copy the login files into the profile.

This shows a problem with decrypting the logins:

NS_ERROR_FAILURE: Couldn't decrypt string 160 crypto-SDR.js:200
decrypt resource://gre/modules/crypto-SDR.js:200
getAllLoginsAsync resource://gre/modules/storage-json.js:383

• https://searchfox.org/mozilla-release/source/toolkit/components/passwordmgr/crypto-SDR.js#169
• https://searchfox.org/mozilla-release/source/toolkit/components/passwordmgr/storage-json.js#353

The details in the searchfox links seem to be about what you said. Is there any solution if the logins can't be decrypted? Otherwise I'll have to manually add the logins to the newest Firefox.

I don't know whether this is applicable to Linux, but...

My thought is that there may have been too many changes between Firefox 49 and 78 for a smooth conversion. You could try installing the Extended Support Release of Firefox 68 and see whether it can convert your files. If so, then try its converted files in Firefox 78.

Installers:

https://www.mozilla.org/firefox/all/#product-desktop-esr

Note: Firefox 68 is aware that different profiles belong to different flavors of Firefox, but you still might want to use a custom install and make sure it uses a different program folder. If you choose to install an older version, choose a Developer Edition or Nightly to avoid profile contamination.

Thank you jscher2000, I really appreciate the advice. I will give that a try.

I wouldn't know what to do without the help here

See also:

• Bug 1607798 - Add a new watershed for Firefox 72.0.2 and update some existing ones to avoid password migration issues when updating to 73+

Jscher2000, just to clarify something. Do you mean I should install the dev edition of 68 or of versions older than 68 if I install them?

Best is probably to install a Firefox 72.0.2 version as that version is meant for migrating older Firefox version properly and use this 72.0.2 version with the Firefox 49 profile backup.

Bug reports related to logins and updating from older Firefox versions.

• Bug 1607798 - Add a new watershed for Firefox 72.0.2 and update some existing ones to avoid password migration issues when updating to 73+
• Bug 1607542 - Stop deleting key3.db in Firefox init
• Bug 1615382 - All saved passwords can't be decrypted (and don't show in about:logins) if the migration to key4.db didn't succeed

Firefox releases on the Mozilla server:

• https://download-installer.cdn.mozilla.net/pub/firefox/releases/72.0.2/

You can install Firefox 72.0.2 in a "firefox-72" folder in your Home directory.
Make sure that you start Firefox 72.0.2 with the Profile Manager and select the Firefox 49 profile.

• https://developer.mozilla.org/en-US/Command_Line_Options

cd ~/firefox-72
./firefox -P

You may have to create a new profile and use "Choose Folder" to register this profile if you do not see this profile in the Profile Manager.
Hopefully you will see the logins in the Password Manager.
If that works then you can copy logins.json and key4.db from this profile to the Firefox 79 profile.

I've managed to get a working key4.db and logins.json pair in the latest version of Firefox. I listened to the instructions above, thank you for helping me.