Gutenberg Templates: Core Blocks List in CPT register

core-blocks-list-cpt-register.php

<?php
[...]

'template' => 
  array(
    array('core/archives'),
    array('core/audio'),
    array('core/block'),
    array('core/button'),
    array('core/categories'),            
    array('core/code'),
    array('core/columns'),
    array( 'core/cover', array(
        'align' => 'center', // Parameters: left, center, right
        'backgroundType' => '???', // Default: image
        'className' => 'attr-cover-test',
        'contentAlign' => 'right', // Parameters: left, center, right
        //'overlayColor' => '',
        'customOverlayColor' => '#ff0000', // Only works if 'overlayColor' has not been set
        'dimRatio' => 90, // opacity: 0 to 100
        'hasParallax' => true, // Parameters: true, false
        'id' => '',
        'title' => 'I am a block placeholder title!',
    ) ),   
    array('core/embed'),    
    array('core/file'),
    array('core/gallery'),
    array('core/heading'),  
    array('core/html'),
    array('core/image'),    
    array('core/latest-comments'),
    array('core/latest-posts'), 
    array('core/list'),
    array('core/media-text'),
    array('core/missing'),  
    array('core/more'),
    array('core/nextpage'),
    array( 'core/paragraph', array(
        //'backgroundColor' => '#000000',
        'customBackgroundColor' => '#000000', // Only works if 'backgroundColor' has not been set
        //'textColor' => '#0099ff',
        'customTextColor' => '#00ff00', // Only works if 'textColor' has not been set
        'fontSize' => 'large', // Parameters: small, normal, medium, large, huge
        //'customFontSize' => '10', Only works if 'fontSize' has not been set
        'dropCap' => true, // // Parameters: true, false
        'align' => 'left', // Parameters: left, center, right
        'className' => 'attr-template-test',
        'placeholder' => 'Add a description',
    ) ),
    array('core/preformatted'),
    array('core/pullquote'),
    array('core/quote'),
    array('core/separator'),
    array('core/shortcode'),
    array('core/spacer'),
    array('core/subhead'),  
    array('core/table'),
    array('core/template'),
    array('core/text-columns'), 
    array('core/verse'),
    array('core/video')
  )
[...]