The pattern parser field next numeric name is of type number but in add part it's assigned to the group name which is of type string without conversion:
Otherwise if regexp or wildcard token is not null:
1. Set name to parser’s next numeric name.
It should be serialized to a string before assignment.
What is the issue with the URL Pattern Standard?
The pattern parser field next numeric name is of type number but in add part it's assigned to the group name which is of type string without conversion:
It should be serialized to a string before assignment.