Hi,
The pubring.kbx~ file is evidently created by moving the existing pubring.kbx to
it and then recreating pubring.kbx. This can be a problem when using the new
gpg-agent forwarding feature. For example, I run my mail client in a FreeBSD
jail that contains my pubring.kbx and an empty private-keys-v1.d directory. In
order to keep pubring.kbx in sync while managing my keyring from the host, I
make pubring.kbx on the host a symlink to the actual pubring.kbx in the jail.
Thus, when the backup is created on the host, it renders my symlink
dysfunctional. I suggest copying pubring.kbx to pubring.kbx~ instead to resolve
this issue.
Thanks,
--Kyle