I installed Ubuntu and then decided to install virtualbox via apt install.
Out of the blue, I am asked this:
┌───────────────────────┤ Configuring Secure Boot ├────────────────────────┐
│ A new Machine-Owner key has been generated for this system to use when │
│ signing third-party drivers. This key now needs to be enrolled in your │
│ firmware, which will be done at the next reboot. │
│ │
│ If Secure Boot validation was previously disabled on your system, │
│ validation will also be re-enabled as part of this key enrollment │
│ process. │
│ │
│ Enroll a new Machine-Owner Key? │
│ │
│ <Yes> <No> │
│ │
└──────────────────────────────────────────────────────────────────────────┘
I have no idea what that means, but it does not sound like something I would have a strong opinion about.
What is the "safe" choice?
The default choice is "No", so I guess it is what most users choose?
Update: I just read all of https://wiki.ubuntu.com/UEFI/SecureBoot but I am still not sure. I vaguely remember a similar step when I installed the OS, so I guess I should have a key already, and creating a new one might cause problems.
Update 2: I just got this prompt again, this time with an intro message saying "UEFI Secure Boot requires additional configuration to work with third-party drivers." I clicked "Next" just to see, but then pressing "Back" unexpectedly made the dialog disappear.