Comment 12 for bug 1826453

Hi Mathieu,
Thanks for the hint! After I changed the Pin-Priority from 400 to 600 in the below file, I successfully installed the *3.22 version:

root@decui-g2-1604:~# cat /etc/apt/preferences.d/proposed-updates
Package: *
Pin: release a=xenial-proposed
Pin-Priority: 600

...

root@decui-g2-1604:~# apt policy grub2-common
grub2-common:
  Installed: 2.02~beta2-36ubuntu3.22
  Candidate: 2.02~beta2-36ubuntu3.22
  Version table:
 *** 2.02~beta2-36ubuntu3.22 600
        600 http://archive.ubuntu.com/ubuntu xenial-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     2.02~beta2-36ubuntu3.21 500
        500 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
     2.02~beta2-36ubuntu3 500
        500 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 Packages

And I can confirm the issue is fixed for "16.04.6 LTS (Xenial Xerus)"!

Now in the VM running on Hyper-V, I get the below as expected (previously I can not see the line with the *3.21 version of grub2):

root@decui-g2-1604:~# dmesg | grep "efifb: framebuffer"
[ 0.472000] efifb: framebuffer at 0xf8000000, mapped to 0xffffc90001c00000, using 3072k, total 3072k

Thank you all for the quick response!