Updating Tunnelblick 3.8.6beta04 and 3.8.6beta05

Updating Tunnelblick 3.8.6beta04 and 3.8.6beta05 does not work properly. When those versions of Tunnelblick attempt to update themselves, the following error message pops up:

How to Update Tunnelblick 3.8.6beta04 and 3.8.6beta05 manually

To update Tunnelblick 3.8.6beta04 or 3.8.6beta05 manually, download the latest beta version of Tunnelblick from the Downloads page and install it normally by double-clicking the Tunnelblick icon. The currently installed version of Tunnelblick will be updated to the new version without changing your configurations and settings.

Why doesn't the update mechanism work?

3.8.6beta04 and 3.8.6beta05 were the first versions of Tunnelblick which were Universal (that is, they run natively on Intel and Apple Silicon systems). They were signed and notarized on macOS 10.14, which does not sign such Universal versions correctly.

Later versions of Tunnelblick are signed and notarized on macOS 11 or later, which sign Universal versions correctly, enabling the update mechanism to work correctly.