Suppress notice messages related to the VCard::getHTML call in mod/display

- Address https://soc.schuerz.at/display/4edd2508-6661-a8d1-f168-b2a245440386

src/Content/Widget/VCard.php

@@ -75,7 +75,7 @@ class VCard
 				$pending = $pcontact['pending'] ?? false;
 			}
 
-			if (!$contact['self'] && Protocol::supportsFollow($contact['network'])) {
+			if (empty($contact['self']) && Protocol::supportsFollow($contact['network'])) {
 				if (in_array($rel, [Contact::SHARING, Contact::FRIEND])) {
 					$unfollow_link = 'unfollow?url=' . urlencode($contact['url']) . '&auto=1';
 				} elseif (!$pending) {