In the MDN page about the “autocomplete” attribute, standard name segments have been defined. However, the options and definitions are not optimal for internationalization. Google x-attributetype offers a good option, namely “surname”, which has no equivalent in the MDN list. I suggest its inclusion and here is why.
Not in all societies, all family members share a name. Naming conventions vary significantly in the world.
In German and English speaking countries, there are family names. A woman often changes her family name when she marries a man and every member of the new family, including children, will share the same family name.
In Spanish and Portuguese speaking countries, this is not the case. Children have one or more given names and two clan names, one from each parent. A woman can change one of her two clan names when marrying, but this is often not done. Given names and clan names are separate sets and recognized as such. Rather than grouping family members, clan names are inherited indirectly from two grand fathers and they are somewhat useful for separating the cousins into two groups, each child usually having two sets of cousins.
In Icelandic, there are no family names like in English and German and no clan names like in Portuguese and Spanish. At birth, a new name is constructed from a parent’s given name: for instance, “Maria’s son” or “Maria’s daughter” if the baby’s mother is called “Maria”. The name of either parent can be used for creating such a segment.
In Javanese (Indonesia), people have no family names, no clan names, no genitive name, and there is a trend towards inherit one name from the father. However, people’s names are better understood as a series of given names since there is no obligation that any name segment be the same as a name of either parent.
Given that scenario, when Spanish/Portuguese speakers, Icelanders, and Indonesians are in German or English-speaking countries, a good compromise between the naming systems is to ask people to split their names in half. The given name is the proper name of that person (proper name) and the surname is a name “above” that one, common to a group of people (common name). The group sharing a name can be “Maria’s children” as in Icelandic, they can be two clans as in “Martín Morales” for Ricky Martin, or a family as in “the Bidens” for Joe Biden. When traveling abroad, Javanese-speaking people can just present their whole name as a given name (proper name) or split their name in half as they find fit if the surname field cannot be left empty.