Help Unregistering a Core Block Type in Gutenberg

Question

I'm trying to unregister core block types in WordPress Gutenberg.

I've used the code provided here: https://github.com/WordPress/gutenberg/blob/master/docs/extensibility/extending-blocks.md#removing-blocks

But I can't get it to work. I feel like there may be a simple step I am missing?

1. I created a plugin which I activated in my WP theme.
2. In my plugin [clore-blocks] folder I created "clore-blocks.php". It contains:

/**
 * Remove certain blocks.
 */
function clore_blacklist_blocks() {
    wp_enqueue_script(
        'clore-blacklist-blocks',
        plugins_url( 'blocks.js', __FILE__ ),
        array( 'wp-blocks' ),
        filemtime( plugin_dir_path( __FILE__ ) . 'blocks.js' ) // Version: filemtime - Gets file modification time.
    );
}
add_action( 'enqueue_block_editor_assets', 'clore_blacklist_blocks' );

3. In blocks.js I have only:

wp.blocks.unregisterBlockType( 'core/verse' );

I thought this would remove the "Verse" block type from being used, but when I go to edit a page with the Gutenberg editor, "Verse" is still there.

When I view the page source from the WP edit page, I can see that my "blocks.js" file is being referenced correctly, but It's just not doing anything... or at least not what I want it to do. Do you have any idea why that is?

Answer 1

Everything works for me with allowed_block_types hook.

Example:

add_filter( 'allowed_block_types', 'my_function' );

function my_function( $allowed_block_types ) {

    return array(
        'core/paragraph'
    );

}

You can insert the above code to your functions.php file to a custom plugin. It removes all blocks except the Paragraph block.

More examples here https://rudrastyh.com/gutenberg/remove-default-blocks.html

Answer 2

Had the same problem following the code suggestion in the Gutenberg docs.

I solved this by adding a wp.domReady() call to the JavaScript code. So, like this:

wp.domReady( function() {
    wp.blocks.unregisterBlockType( 'core/verse' );
});

Now, the 'verse' block is gone from the block editor.

I think this has to do with the order of loading javascript files in the admin. The unregisterBlockType should be called after the block editor has loaded.

Hope this helps!

Thanks to PayteR for the suggestion and see https://wordpress.org/gutenberg/handbook/designers-developers/developers/filters/block-filters/#using-a-blacklist for more info.

Answer 3

Here's another approach using PHP hook on how to disable specific block on the Gutenberg editor:

<?php
function disable_specific_blocks( $allowed_block_types, $post ) {
    // An array of block names to disable
    $disabled_blocks = array(
        'core/table',
        'core/image',
        'core/gallery',
    );
  
    // Use this condition to disable blocks on certain post types, otherwise you can remove this IF condition
    if ( $post->post_type === 'post' ) {
        $allowed_block_types = array_diff( $allowed_block_types, $disabled_blocks );
    }

    return $allowed_block_types;
}
add_filter( 'allowed_block_types_all', 'disable_specific_blocks', 10, 2 );
?>

You can check this guide on how to restrict specific blocks on the WordPress block editor for more information.