diff --git a/includes/SpecialLintErrors.php b/includes/SpecialLintErrors.php
index 285538e2..fcd77da7 100644
--- a/includes/SpecialLintErrors.php
+++ b/includes/SpecialLintErrors.php
@@ -210,9 +210,11 @@ class SpecialLintErrors extends SpecialPage {
 		);
 		if ( $request->getCheck( 'wpNamespaceRestrictions' ) ) {
 			$namespaceRequestValues = $request->getRawVal( 'wpNamespaceRestrictions' );
-			$namespaceIDs = array_map( 'intval', explode( "\n", $namespaceRequestValues ) );
-			// Security measure: only allow active namespace IDs to reach the query
-			$namespaces = array_values( array_intersect( $activeNamespaces, $namespaceIDs ) );
+			if ( strlen( $namespaceRequestValues ) > 0 ) {
+				$namespaceIDs = array_map( 'intval', explode( "\n", $namespaceRequestValues ) );
+				// Security measure: only allow active namespace IDs to reach the query
+				$namespaces = array_values( array_intersect( $activeNamespaces, $namespaceIDs ) );
+			}
 		}
 		return $namespaces;
 	}