At least Twitter <https://cards-dev.twitter.com/validator> requires og property to be first.
<title property="og:name"><?= htmlspecialchars($Page->safetitle) ?></title>
<?php } ?>
<?php if ($Page->teaser) { ?>
- <meta name="description" property="og:description" content="<?= preg_replace('/\s+/', ' ', strip_tags($Page->teaser)) ?>" />
+ <meta property="og:description" name="description" content="<?= preg_replace('/\s+/', ' ', strip_tags($Page->teaser)) ?>" />
<?php } ?>
<meta name="viewport" content="width=device-width" />
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