Comment 20 for bug 1991812

I tested it on my end on Focal:

$ dpkg-query --show frr
frr 7.2.1-1

$ id syslog
id: ‘syslog’: no such user

$ apt-cache policy frr
frr:
  Installed: 7.2.1-1
  Candidate: 7.2.1-1ubuntu0.2
  Version table:
     7.2.1-1ubuntu0.2 500
        500 http://ch.archive.ubuntu.com/ubuntu focal-proposed/universe amd64 Packages
 *** 7.2.1-1 500
        500 http://ch.archive.ubuntu.com/ubuntu focal/universe amd64 Packages
        100 /var/lib/dpkg/status

$ sudo apt-get install frr
Reading package lists... Done
Building dependency tree
Reading state information... Done
Suggested packages:
  frr-doc
The following packages will be upgraded:
  frr
1 upgraded, 0 newly installed, 0 to remove and 159 not upgraded.
Need to get 2,350 kB of archives.
After this operation, 0 B of additional disk space will be used.
Get:1 http://ch.archive.ubuntu.com/ubuntu focal-proposed/universe amd64 frr amd64 7.2.1-1ubuntu0.2 [2,350 kB]
Fetched 2,350 kB in 0s (75.3 MB/s)
debconf: delaying package configuration, since apt-utils is not installed
(Reading database ... 100330 files and directories currently installed.)
Preparing to unpack .../frr_7.2.1-1ubuntu0.2_amd64.deb ...
Unpacking frr (7.2.1-1ubuntu0.2) over (7.2.1-1) ...
Setting up frr (7.2.1-1ubuntu0.2) ...
Installing new version of config file /etc/logrotate.d/frr ...
addgroup: The group `frrvty' already exists as a system group. Exiting.
addgroup: The group `frr' already exists as a system group. Exiting.
Warning: The home dir /nonexistent you specified can't be accessed: No such file or directory
The system user `frr' already exists. Exiting.
Processing triggers for systemd (245.4-4ubuntu3.17) ...

It works!
I'll repeat the test on Jammy, but I'm confident it'll work there too.
Thanks @Andreas.

When can I see this uploaded to (focal|jammy)-updates?