I'm using CUPS 2.3.1 on Ubuntu 20.04

Suppose I have the following queues (all of them with no jobs):

Q1, Q2, Q3, Q4, Q5

and this file (file.ipp):

{
OPERATION CUPS-Get-Printers
GROUP operation-attributes-tag
ATTR charset attributes-charset utf-8
ATTR language attributes-natural-language en
ATTR keyword requested-attributes printer-name,printer-state,queued-job-count
STATUS successful-ok
DISPLAY printer-name
DISPLAY printer-state
DISPLAY queued-job-count
}

when I run this command

ipptool ipp://localhost file.ipp

I get an output like this

printer-name printer-state queued-job-count

Q1 idle
Q3 idle
Q5 idle

Notice that queues Q2 and Q4 didn't show up and the job count is empty (and not 0 as expected)

I've got the same behaviour when running with -c, but the correct one when using -X or -t.

Now, if I change the order of the DISPLAY directives as follows

{
OPERATION CUPS-Get-Printers
GROUP operation-attributes-tag
ATTR charset attributes-charset utf-8
ATTR language attributes-natural-language en
ATTR keyword requested-attributes printer-name,printer-state,queued-job-count
STATUS successful-ok
DISPLAY queued-job-count
DISPLAY printer-name
DISPLAY printer-state
}

the output correctly shows all queues and the job count as 0s:

queued-job-count printer-name printer-state

0 Q1 idle
0 Q2 idle
0 Q3 idle
0 Q4 idle
0 Q5 idle