Are Container Queries supported on AMP?

Question

I don't find documentation ruling out the use of Container Queries on AMP, but by using the AMP for Wordpress plugin, they are somehow filtered out of the amp-custom css tag, e.g.:

.parent {
  ...
  container-type: inline-size;
}
@container (max-width: $sm) {
  .child {
    display: flex;
    flex-direction: column;
  }
}

Would only output

.parent {
  ...
  container-type: inline-size;
}

Can anyone point me to more information about the topic? or a way to make AMP for Wordpress allow the @container part?