WordPressのプレビューが効かない場合の対応

function.phpに下記を書き込み確認。

// プレビュー制御（プレビューがNot Found になる場合コメントを外す）
function remove_param( $url ) {
    $url = remove_query_arg( 'post_format', $url );
    return $url;
}
add_filter( 'preview_post_link', 'remove_param', 100 );

参考サイト

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Warning: Illegal string offset 'content_site_url' in /home/favorite-color/www/wp-note/cms/wp-content/themes/lionblog/single.php on line 119

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Warning: Illegal string offset 'content_site_url' in /home/favorite-color/www/wp-note/cms/wp-content/themes/lionblog/single.php on line 125

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