<?php
while ($result = mysqli_fetch_assoc($query)) {?>
    <div class="content">
       <div class="block-smallContainer" style="display: none;">
         <a href="#">
            <i class="far fa-trash-alt">
               <span>Удалить</span>
            </i>
         </a>
       </div>
    </div>
    <div class="footer">
        <a class="other-btn" href="#"><i class="fas fa-ellipsis-h other"></i></a>
    </div>
<?php
}?>

$(".content").on("click", function () {
    event.preventDefault();
    $(this).prev(".block-smallContainer").slideToggle(100);
})