BuddyPress.org

Hello

I see following error on BP 10.2.0

Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, class "BP_Nouveau_Object_Nav_Widget" not found in /mnt/web213/b1/68/511611068/htdocs/wp-includes/class-wp-hook.php:307 Stack trace: #0 /mnt/web213/b1/68/511611068/htdocs/wp-includes/class-wp-hook.php(331): 

What can be source of this problem. I use my own custom theme.