The URL you opened was intended for testing Instant View template for this website:

https://www.facebook.com/plugins/post.php?href=https://www.facebook.com/metpleziernaarschool/posts/pfbid02os3LpJ2ZiRLsnSbGVQDixpGDreNtahP716X5MdXiSp8mKUgSw5qasrK77F5Z27S3l