--- Shaarli/index.php	2017-01-20 16:47:36.000000000 +0100
+++ index.php	2017-02-11 23:27:22.510042000 +0100
@@ -1821,11 +1821,14 @@
             $path = parse_url($url,PHP_URL_PATH);
             if ("/talks/" !== substr($path,0,7)) return array(); // This is not a single video URL.
         }
+    }
         $sign = hash_hmac('sha256', $url, $conf->get('credentials.salt')); // We use the salt to sign data (it's random, secret, and specific to each installation)
-        return array('src'=>index_url($_SERVER).'?do=genthumbnail&hmac='.$sign.'&url='.urlencode($url),
+        $thumbname=hash('sha1',$url).'.gif';
+        $filepath = $conf->get('resource.thumbnails_cache').'/'.$thumbname;
+        if (sha1_file($filepath) != '48d45d7ada69f9f858849bbd6e459f66c9694ee7')
+                return array('src'=>index_url($_SERVER).'?do=genthumbnail&hmac='.$sign.'&url='.urlencode($url),
                      'href'=>$href,'width'=>'120','style'=>'height:auto;','alt'=>'thumbnail');
-    }
-
+	
     // For all other, we try to make a thumbnail of links ending with .jpg/jpeg/png/gif
     // Technically speaking, we should download ALL links and check their Content-Type to see if they are images.
     // But using the extension will do.
@@ -2154,19 +2157,33 @@
     else
     {
         // For all other domains, we try to download the image and make a thumbnail.
-        // We allow 30 seconds max to download (and downloads are limited to 4 Mb)
-        list($headers, $content) = get_http_response($url, 30);
-        if (strpos($headers[0], '200 OK') !== false) {
-            $filepath = $cacheDir .'/'.$thumbname;
-            // Save image to cache.
-            file_put_contents($filepath, $content);
-            if (resizeImage($filepath))
-            {
-                header('Content-Type: image/jpeg');
-                echo file_get_contents($filepath);
-                return;
-            }
-        }
+	list($headers, $content) = get_http_response($url,30);  // We allow 30 seconds max to download (and downloads are limited to 4 Mb)
+	if (strpos($headers[0], '200 OK') !== false) 
+	{
+		// Extract the link to the thumbnail
+		$doc = new DOMDocument();
+		libxml_use_internal_errors(true);
+		$doc->loadHTML($content);
+		foreach( $doc->getElementsByTagName('meta') as $meta )
+			if ($meta->getAttribute('property') == 'og:image')
+				$imageurl=$meta->getAttribute('content');
+
+		if (!empty($imageurl))
+		{   // Let's download the image.
+			list($headers, $content) = get_http_response($imageurl, 20);
+			if (strpos($headers[0], '200 OK') !== false) 
+			{
+				$filepath = $conf->get('resource.thumbnails_cache').'/'.$thumbname;
+				file_put_contents($filepath,$content); // Save image to cache.
+				if (resizeImage($filepath))
+				{
+					header('Content-Type: image/jpeg');
+					echo file_get_contents($filepath);
+					return;
+				}
+			}
+		}
+	}
     }