Adding Alt Tag and Dimensions columns to Media Library

You don’t have to create a new function each time you add a new admin column. You can use below functions to show both your media data in separate admin columns.

function column_id($columns) {
    $columns['media_alt'] = __('Alt');
    $columns['media_dimensions'] = __('Dimensions');
    return $columns;
} 
add_filter( 'manage_media_columns', 'column_id' );
 
function column_id_row($columnName, $columnID){
    if ( $columnName == 'media_alt') {
        $image_alt = get_post_meta($columnID, '_wp_attachment_image_alt', true);
        echo $image_alt;
    }
    if ( $columnName == 'media_dimensions') {
        $image_size = wp_get_attachment_image_src($columnID, 'full');
        if ( $image_size ) {
            echo $image_size[1] . ' x ' . $image_size[2];
        }
    }
}
add_filter( 'manage_media_custom_column', 'column_id_row', 10, 2 );