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force one column layout on edit screen

//Force one column layout in edit screen

function so_screen_layout_columns( $columns ) {
    $columns['post'] = 1;
    return $columns;
}
add_filter( 'screen_layout_columns', 'so_screen_layout_columns' );

function so_screen_layout_post() {
    return 1;
}
add_filter( 'get_user_option_screen_layout_post', 'so_screen_layout_post' );