flexbox justify-self: flex-end が機能しない？重複

.row {
  border: 1px solid black;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.left,
.right {
  display: inline-block;
  background-color: yellow;
}

.right {
  justify-self: flex-end;
}

<div class="row">
  <!--<div class="left">left</div>-->
  <div class="right">right</div>
</div>

.row {
  border: 1px solid black;
  display: flex;
  align-items: center;
}
.left,
.right {
  background-color: yellow;
}
.right {
  margin-left: auto;
}

<div class="row">
  <!--<div class="left">left</div>-->
  <div class="right">right</div>
</div>