Pay With Paypal: Add fallback code blocks for different contexts.

[kwight]

On WordPress.com, the Reader, Masterbar notifications, and email notifications are all different contexts in which Gutenberg blocks can be viewed, and they've each got their own limitations and issues with what to render (for example, iframes and other elements are impossible in email, while certain interactions like PayPal purchase buttons are inappropriate in notifications). Blocks need to be able to produce fallback markup when displaying in these different contexts.

The render_callback property can be used directly in blocks we control to define these fallbacks. Let's add context identifiers and code blocks for the Pay With PayPal block, which will also stand as an example for how to handle other blocks.

register_block_type( 'namespace/my-block', [
  'render_callback' => 'render_block',
] );
 
function render_block( $attributes, $content ) {
  if ( $is_email_context ) {
    // Return email fallback.
  }
  if ( $is_reader_context ) {
    // Return reader fallback.
  }
  if ( $is_notifications_context ) {
    // Return notifications fallback.
  }
 
  return $content;
}

See: paYKcK-FI-p2
See: 217-gh-dotcom-manage

[kwight]

Oops, duplicate of Automattic/jetpack#17161