Supplying invalid values (accidentally since I missed the space!) results in attempting to use the value, instead of validating it before submitting, and the response 'Invalid account or key', though I think it'd be more user friendly if the account name box failed regex validation. There may be a reason to support other characters for custom domains, but since both requests are defaulting to the normal endpoints I think the logic could be split if there's a suffix.
{description: "System.UriFormatException: 'Invalid URI: The hostname could not be parsed.'",…}
description: "System.UriFormatException: 'Invalid URI: The hostname could not be parsed.'"
statusText: "Invalid URI: The hostname could not be parsed."
{"description":"System.AggregateException: 'Retry failed after 6 tries. Retry settings can be adjusted in ClientOptions.Retry. (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443))'","statusText":"Retry failed after 6 tries. Retry settings can be adjusted in ClientOptions.Retry. (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443)) (Name or service not known (fakenadddd.queue.core.windows.net:443))"}