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// RETIRA ATRIBUTO WIDHT E HEIGHT DAS IMAGENS 

function remove_image_size_attributes( $html ) {
    return preg_replace( '/(width|height)="\d*"/', '', $html );
}
 
// Remove image size attributes from post thumbnails
add_filter( 'post_thumbnail_html', 'remove_image_size_attributes' );
 
// Remove image size attributes from images added to a WordPress post
add_filter( 'image_send_to_editor', 'remove_image_size_attributes' );