Find the file: /wp-includes/http.php

Search:

$same_host = strtolower( $parsed_home['host'] ) === strtolower( $parsed_url['host'] );

Replace with:

if ( isset( $parsed_home['host'] ) ) { $same_host = ( strtolower( $parsed_home['host'] ) === strtolower( $parsed_url['host'] ) || 'localhost' === strtolower( $parsed_url['host'] ) ); } else { $same_host = false; };

Search:

if ( 127 === $parts[0] || 10 === $parts[0] || 0 === $parts[0]

Replace with:

if ( 127 === $parts[0] || 10 === $parts[0] || 0 === $parts[0] || 0 === $parts[0]

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