Consider this code:

void func(int i, int j);
void func(int i, double d);

int main()
{
func(0, /* request function hint here */
}

Make sure you have clangd running on this file and request a function hint at the specified location.
You will get two signatures, as expected. In the first one, the second parameter correctly has a bold font, indicating the parameter corresponding to the current cursor position. But if you switch to the next signature, the active parameter is not marked there.