g_string_new() not in GString's documentation
I was looking in https://docs.gtk.org/glib/struct.String.html and couldn't find the constructor, only to find https://docs.gtk.org/glib/func.string_new.html via an external search engine. I'd expect the constructor to be with its type.
Same for https://docs.gtk.org/glib/func.string_new_len.html and https://docs.gtk.org/glib/func.string_sized_new.html (shouldn't it be called string_new_sized()
? it's too late now I assume).