diff --git a/co-authors-plus.php b/co-authors-plus.php
index 3ea6cc68..1001594e 100755
--- a/co-authors-plus.php
+++ b/co-authors-plus.php
@@ -1860,8 +1860,8 @@ public function filter_pre_get_avatar_data_url( $args, $id ) {
 		}
 
 		// Do not filter when on the user screen
-		$current_screen = get_current_screen();
-		if ( isset( $current_screen->parent_base ) && 'users' == $current_screen->parent_base ) {
+		$current_screen = function_exists( 'get_current_screen' ) ? get_current_screen() : null;
+		if ( ! is_null( $current_screen ) && isset( $current_screen->parent_base ) && 'users' === $current_screen->parent_base ) {
 			return $args;
 		}