This question already has an answer here:
I upgraded my PHP to 7.0 and after this I have this message in the header of my website:
Warning: Declaration of description_walker::start_el($output, $item, $depth, $args) should be compatible with Walker_Nav_Menu::start_el(&$output, $item, $depth = 0, $args = Array, $id = 0) in /homepages/2/d444683358/htdocs/wp-content/themes/zend/functions.php on line 59
Here is the line 59 in functions.php:
$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
I'm not a coder so not sure what needs to be done to fix this?
Thanks for your help