diff --git a/controllers/ViewPhoto.php b/controllers/ViewPhoto.php
index fb151a0..0b8a6b8 100644
--- a/controllers/ViewPhoto.php
+++ b/controllers/ViewPhoto.php
@@ -50,13 +50,12 @@ class ViewPhoto extends HTMLController
 		if (isset($_GET['by']))
 		{
 			// Let's first verify that the filter is valid
-			$contributors = array_filter($tag->getContributorList(), fn($el) => $el['slug'] === $_GET['by']);
-			if (count($contributors) !== 1)
+			$user = Member::fromSlug($_GET['by']);
+			if (!$user)
 				throw new UnexpectedValueException('Invalid filter for this album or tag.');
 
 			// Alright, let's run with it then
-			$filter = reset($contributors);
-			$page->setActiveFilter($filter['slug']);
+			$page->setActiveFilter($user->getSlug());
 		}
 
 		$this->page->adopt($page);
diff --git a/models/Asset.php b/models/Asset.php
index 9510735..c2973c7 100644
--- a/models/Asset.php
+++ b/models/Asset.php
@@ -723,9 +723,8 @@ class Asset
 		}
 
 		// Take active filter into account as well
-		if (!empty($activeFilter))
+		if (!empty($activeFilter) && ($user = Member::fromSlug($activeFilter)) !== false)
 		{
-			$user = Member::fromSlug($activeFilter);
 			$where[] = 'id_user_uploaded = {int:id_user_uploaded}';
 			$params['id_user_uploaded'] = $user->getUserId();
 		}
diff --git a/models/User.php b/models/User.php
index f690f27..b69790d 100644
--- a/models/User.php
+++ b/models/User.php
@@ -75,6 +75,11 @@ abstract class User
 		return $this->ip_address;
 	}
 
+	public function getSlug()
+	{
+		return $this->slug;
+	}
+
 	/**
 	 * Returns whether user is logged in.
 	 */