[$] Linux and Secure Boot certificate expiration

Linux users who have Secure Boot
enabled on their systems knowingly or unknowingly rely on a key from
Microsoft that is set to expire in September. After that point, Microsoft
will no longer use that key to sign the shim
first-stage UEFI bootloader that is used by Linux distributions to boot the
kernel with Secure Boot. But the replacement key, which has been available
since 2023, may not be installed on many systems; worse yet, it may require
the hardware vendor to issue an update for the system firmware, which may
or may not happen. It seems that the vast majority of systems will not be
lost in the shuffle, but it may require extra work from distributors and
users.