Extending a placeholder from a media query outputs nothing

[whaaaley]

input.scss

@media (min-width: 100px) {
  .parent > %child {
    color: blue;
  }
}

.foo {
  @extend %child;
}

[libsass 3.5.5]

ruby sass 3.4.21

@media (min-width: 100px) {
  .parent > .foo {
    color: blue;
  }
}

Spec added sass/sass-spec#894