data is here subprojects={"RFv6bJMG2dmiBqWNZX8O":{"content":"this is ・・data"}}
console.log("subprojects=" + JSON.stringify(subprojects));
const SubList = ({ subprojects }) => {
if(subprojects){
  return (
    <div className="project-list section">
      {subprojects &&
        subprojects.map((subproject) => {
          return (
            <div>
              {subproject.id}
            </div>
          );
        })}
    </div>
  );}
  else{
The result is TypeError: subprojects.map is not a function
 
     
    