Show Bootstrap Sizers in Wordpress

functions.php

<?php

  function getBootstrapBreakpoints() {
    return array(
      'xs',
      'sm',
      'md',
      'lg',
      'xl',
    );
  }

  function get_display_classes($showSizes, $show = 'block', $hide = 'none'){
    $classes = [];
    foreach ($showSizes as $breakpoint => $display) {
      if ($display) {
        $classes[] = "d-$breakpoint-$show";
      } else {
        if ($breakpoint === 'xs') {
          $classes[] = "d-$hide";
        } else {
          $classes[] = "d-$breakpoint-$hide";
        }
      }
    }
    return implode(' ', $classes);
  }


  function showSizers() {
    if (!empty($_REQUEST['showSizers'])) {
      echo '<div class="fixed-bottom show-sizers">';
      $sizes = getBootstrapBreakpoints();
      $allOff = [];
      foreach ($sizes as $size) {
        $allOff[$size] = false;
      }
      foreach ($sizes as $size) {
        $theseBreaks = $allOff;
        $theseBreaks[$size] = true;
        $classes = get_display_classes($theseBreaks, 'inline-block');
        echo "<div class=\"$classes btn btn-info btn-lg sizer\">$size</div>";
      }

      echo '</div>';
    }
  }
  add_action( 'wp_footer', 'showSizers' );




?>