Add width and height SVG upload on WordPress

functions.php

/* ------------------------------------------------------------------------------- */
/* Add media data (width and height) to SVG upload
/* https://wordpress.stackexchange.com/a/256701/164915
/* Alternative: https://wordpress.org/plugins/enable-svg-uploads/
/* ------------------------------------------------------------------------------- */

function svg_meta_data($data, $id){

  $attachment = get_post($id); // Filter makes sure that the post is an attachment
  $mime_type = $attachment->post_mime_type; // The attachment mime_type

  //If the attachment is an svg

  if($mime_type == 'image/svg+xml'){

    //If the svg metadata are empty or the width is empty or the height is empty
    //then get the attributes from xml.

    if(empty($data) || empty($data['width']) || empty($data['height'])){

        $xml = simplexml_load_file(wp_get_attachment_url($id));
        $attr = $xml->attributes();
        $viewbox = explode(' ', $attr->viewBox);
        $data['width'] = isset($attr->width) && preg_match('/\d+/', $attr->width, $value) ? (int) $value[0] : (count($viewbox) == 4 ? (int) $viewbox[2] : null);
        $data['height'] = isset($attr->height) && preg_match('/\d+/', $attr->height, $value) ? (int) $value[0] : (count($viewbox) == 4 ? (int) $viewbox[3] : null);
    }

  }

  return $data;

}
add_filter('wp_update_attachment_metadata', 'svg_meta_data', 10, 2);



/* ------------------------------------------------------------------------------- */
/* Edit get_attachment_image to add width and height on print
/* https://wordpress.stackexchange.com/a/255634/164915
/* ------------------------------------------------------------------------------- */

function fix_wp_get_attachment_image_svg($image, $attachment_id, $size, $icon) {
  if (is_array($image) && preg_match('/\.svg$/i', $image[0]) && $image[1] <= 1) {
      if(is_array($size)) {
          $image[1] = $size[0];
          $image[2] = $size[1];
      } elseif(($xml = simplexml_load_file($image[0])) !== false) {
          $attr = $xml->attributes();
          $viewbox = explode(' ', $attr->viewBox);
          $image[1] = isset($attr->width) && preg_match('/\d+/', $attr->width, $value) ? (int) $value[0] : (count($viewbox) == 4 ? (int) $viewbox[2] : null);
          $image[2] = isset($attr->height) && preg_match('/\d+/', $attr->height, $value) ? (int) $value[0] : (count($viewbox) == 4 ? (int) $viewbox[3] : null);
      } else {
          $image[1] = $image[2] = null;
      }
  }
  return $image;
} 
add_filter( 'wp_get_attachment_image_src', 'fix_wp_get_attachment_image_svg', 10, 4 );