After today’s upgrade of ‘apt’ package up to version 2.9.16 on Sparky testing “Seven Sisters” based on Debian testing “Trixie” ONLY (not stable, not oldstable), you can find such APT issue: To fix it, do: Copy Sparky GPG key: Change the GPG key in the source list: from: to: Then refresh package list and upgrade packages: or: or…
