force http canonical tag on https pages

At present all https pages have their own canonical tags referencing https, which is incorrect, they should be referencing the http versions.

e.g:

https://www.example.com

has the following canonical tag:

<link rel="canonical" href="https://www.example.com" />

How can we make the canonical tags on https pages use the http URLs?

You can change it using following code, add it in your theme function.php or in plugin.

remove_action ( 'wp_head' , 'rel_canonical' ) ;
add_action ( 'wp_head' , 'my_rel_canonical' ) ;

function my_rel_canonical () {
    ob_start () ;
    rel_canonical () ;
    $rel_content = ob_get_contents () ;
    ob_end_clean () ;
    echo str_replace ( "https:" , "http:" , $rel_content ) ;
}