Testing steps
Enable revealing IP addresses for temporary accounts in preferences

Testing notes
First make sure that revealing IP addresses for temporary accounts is enable in preferances.
I tested by going to Special:Block, and then inputting a temporary user in the target user textbox.
I tested that I can see the IP address below the text field
I checked that 'and' only separates the last two IPs and the rest are separated by ','
I checked that there are no errors on the page/in console while testing this.

@GMikesell-WMF , IP Masking: Wrong format from a blocked message on a Temp User in German has been resolved

@GMikesell-WMF this looks odd and yes it shouldn't look this way. could we please create a ticket for this?

@Tchanders I have created the ticket T327888

Added this ticket https://phabricator.wikimedia.org/T327737 as requested from code review.

The sources used by https://whois-referral.toolforge.org/gateway.py are regional internet regional internet registries and will hold the source of truth for IPs.

what you are looking into and why
We are trying to see if we could get and show IP range and CIDR data in IPInfo.
This comment summarises what is required and mostly why. https://phabricator.wikimedia.org/T316193#8299917

Testing notes

The work on this ticket has moved to https://phabricator.wikimedia.org/T322664

moving this back to in progress as Investigate new approach, possible going to abandon the patch and decline this task. just trying to create relevant task before I close this one.

Testing notes

@Tchanders and @Dreamy_Jazz , I was also unable to reproduce(though I am not confident I followed the correct steps). should we close this ticket or are further investigations still needed?

@Dreamy_Jazz ,no, I assigned it to myself to check if I will be able to replicate, I will be happy to review your patch once its ready for review. Thank you for working on this.

Thank you all, I am planning to attend another training session soon and become a regular deployer.

In T318893#8329206, @Tchanders wrote:

As @dom_walden noted, we could remove this dependency on GlobalBlocking again, once T257701: Add global blocks into CompositeBlocks rather than treating them separately is done, since User::getBlock will get global blocks too.

@TThoabala Would you mind filing a follow-up task and linking that here? Thanks!

In T318877#8329495, @Tchanders wrote:

@GMikesell-WMF @TThoabala Were you able to meet and work out what the problem was?

In T321216#8329739, @Tchanders wrote:

FAO @Cyndymediawiksim and @TThoabala, who have both experienced this. Could you possibly add which page(s) you experienced it from?