diff --git a/src/Model/Contact.php b/src/Model/Contact.php
index a9ef2276ab..4f449a1fa3 100644
--- a/src/Model/Contact.php
+++ b/src/Model/Contact.php
@@ -2301,7 +2301,7 @@ class Contact
 			return;
 		}
 
-		if (!Network::isValidHttpUrl($avatar)) {
+		if (!empty($avatar) && !Network::isValidHttpUrl($avatar)) {
 			Logger::warning('Invalid avatar', ['cid' => $cid, 'avatar' => $avatar]);
 			$avatar = '';
 		}
diff --git a/src/Protocol/ActivityPub/Processor.php b/src/Protocol/ActivityPub/Processor.php
index 930c31a0d3..21be0f6379 100644
--- a/src/Protocol/ActivityPub/Processor.php
+++ b/src/Protocol/ActivityPub/Processor.php
@@ -877,10 +877,10 @@ class Processor
 	{
 		if (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/markdown')) {
 			$item['title'] = strip_tags($activity['name'] ?? '');
-			$content = Markdown::toBBCode($activity['content']);
+			$content = Markdown::toBBCode($activity['content'] ?? '');
 		} elseif (!empty($activity['mediatype']) && ($activity['mediatype'] == 'text/bbcode')) {
-			$item['title'] = $activity['name'];
-			$content = $activity['content'];
+			$item['title'] = $activity['name'] ?? '';
+			$content = $activity['content'] ?? '';
 		} else {
 			// By default assume "text/html"
 			$item['title'] = HTML::toBBCode($activity['name'] ?? '');