On 16.04 and using GNOME Shell not Unity, I wanted to import a *.pem for a custom root cert, but as the "Passwords & Keys" (seahorse) app said I had to unlock a locked keyring to which I could not remember the password (perhaps after the last update, or due to the change of shell?).
Following How to recover/reset forgotten Gnome Keyring Password? I have removed rm ~/.local/share/keyrings/login.keyring
(which was the right thing to do?) and as that didn't work, it still asked for a password to unlock the keyring (did I just forget to logout/login?), I've then also removed rm ~/.local/share/keyrings/user.keystore
(was that dumb?).
But now the Import button is greyed out when I try to import the *.pem, saying "Cannot import because there are no compatible importers" in a hover.
And in my "Passwords & Keys" the "Root CA certificates" & "Gnome 2 Key storage", visible e.g. here How migrate my keyring (containing ssh passprases, nautilus remote filesystem, pgp passwords) and network manager connections?, are gone:
How do I get them back, so that I can import that *.pem?