I did the steps, but it seems there is an error at the end of the command sudo dpkg -i linux*.deb
Adding boot menu entry for UEFI Firmware Settings done Errors were encountered while processing: linux-headers-5.12.4-051204-generic I ignored it. but then when I try to boot using the new kernel, I encounter this error error: /boot/vmlinuz-5.12.4-051204-generic has invalid signature. error: you need to lad the kernel first -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1928656 Title: [i915] Horizontal lines of flickering random pixels on Comet Lake To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-signed-hwe-5.8/+bug/1928656/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs