I’m trying code in your link.
I modify as this.
/**
* Change the PayPal button image on the Paid Memberships Pro - Membership Checkout page.
*
* You can add this recipe to your site by creating a custom plugin
* or using the Code Snippets plugin available for free in the WordPress repository.
* Read this companion article for step-by-step directions on either method.
* https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
*/
function my_pmpro_paypal_button_image( $url ) {
return 'https://www.paypalobjects.com/webstatic/en_US/i/buttons/checkout-logo-large.png';
}
add_filter( 'pmpro_paypal_button_image', 'my_pmpro_paypal_button_image' );
it doesn’t work.
I think because it is related to my_pmpro_paypal_button_image, I use paypal express checkout
In inspect element I see the button is
<input type="image" id="pmpro_btn-submit-paypalexpress" class="pmpro_btn-submit-checkout" value="Paga con PayPal ?" src="https://www.paypalobjects.com/webstatic/en_US/i/buttons/checkout-logo-medium.png">