Plugin Author
Nico
(@nico23)
<meta itemprop="thumbnailUrl" content="http://gulmen-promo.com/wp-content/uploads/2018/04/colordyane.mp4_snapshot_00.00.jpg"><video controls="" controlslist="nodownload" preload="metadata" poster="http://gulmen-promo.com/wp-content/uploads/2018/04/colordyane.mp4_snapshot_00.00.jpg" src="http://gulmen-promo.com/wp-content/uploads/2018/04/colordyane.mp4" class="arve-video fitvidsignore"></video>
Can’t confirm that, this is the code from your site. All thumbnail URL point to images on HTTP
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