Results of upgrading intel-microcode package to 3.20200609.0ubuntu0.20.04.2:
1) First reboot was successful (without dis_ucode_ldr flag)
2) Second and following reboots froze again, the behaviour is now the same as stated in #1883002.
3) Workaround: Grub's dis_ucode_ldr flag fixes the problem, at least on a temporary basis.
Correct, Ubuntu 20.04 LTS/focal.
Results of upgrading intel-microcode package to 3.20200609. 0ubuntu0. 20.04.2:
1) First reboot was successful (without dis_ucode_ldr flag)
2) Second and following reboots froze again, the behaviour is now the same as stated in #1883002.
3) Workaround: Grub's dis_ucode_ldr flag fixes the problem, at least on a temporary basis.