I noticed this earlier and have reported it :) I will let you know what I find out. It actually happens with punctuation after the name as well ;)

I've spoken with about this and it sounds like there may not be a solution. It might be one of those things where we offer a free name change, or you can choose to keep the pet name but accept that the URL will not work correctly. I will try to look for other solutions, but it sounds like we may end up disallowing it. I'll update again once there is a concrete answer.

They used to work, but only due to a (rather severe) flaw in our site security. Luckily, no one had exploited this flaw, and we fixed it as soon as we realized. However, the fix also inadvertently disabled this feature. This is also why we may not be able to restore it.

I'd wait for our decision to be finalized, unless you want to spend the CSC. If we end up disallowing it, we will probably offer free name changes to be fair, so if you wait then you can save the CSC.

Hello, back with a big update.

Unfortunately, we are not able to resolve the issue in another way. Pet names beginning with a period (.) will not be allowed after this point.

If you have a pet with a name like this, you are not required to change it; however, we will not be able to fix the issues around the name. You may file a ticket for a free name change for any pets affected. Simply let the UA know what pet(s) you need changed and what names you want for them.

Your Pets page will show a notice if you have any pets with names that break the current naming rules, along with a link for filing a ticket should you wish to change the name for free.

We sincerely apologize for the inconvenience.

At the end or middle should be fine. It seems to cause problems only when it is the first character.