NO. Whatever the Whonix repository , I get this output from update-tobrowser":
## Verifying GPG signature.
## Not using the user's GPG keyring also ensures, that the key can be only
## signed by the GPG keys we added. Signatures from random people from the
## user's keyring will be ignored.
gpg: Signature made Fri 16 Jan 2015 08:28:57 AM UTC using RSA key ID D40814E0
gpg: Can't check signature: public key not found
[ERROR] [torbrowser] GPG download signature could NOT be verified.
Tor Browser update failed! Try again later.
In the host, torbrowser-launcher cannot update either (“SIGNATURE VERIFICATION FAILED! You might be under attack…”).
Installed torbrowser-launcher in two virtual machines, Debian jessie and Ubuntu 14.04, it works. I really don’t know, but I’d like to investigate a little more before wiping the disk.
Did you “apt get dist-upgrade” from testers or developers repository once before? Because technically in testers and developres have much higher version numbers, but not yet the new key file. If you later switch to the stable repository, it won’t downgrade [without special commands].
The fix is in tb-updater version 3:0.6.2-1.
What’s your tb-updater version? Check.
dpkg -l | grep tb-updater
Got this file on your disk?