disable-gutenberg.php

<?php
/*
Plugin Name: Disable Gutenberg
Plugin URI: https://www.littlebizzy.com/plugins/disable-gutenberg
Description: Disables block editor entirely
Version: 2.0.0
Requires PHP: 7.0
Author: LittleBizzy
Author URI: https://www.littlebizzy.com
License: GPLv3
License URI: http://www.gnu.org/licenses/gpl-3.0.html
GitHub Plugin URI: littlebizzy/disable-gutenberg
Primary Branch: master
*/

// prevent direct access
if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

// disable wordpress.org updates for this plugin
add_filter( 'gu_override_dot_org', function( $overrides ) {
    $overrides[] = 'disable-gutenberg/disable-gutenberg.php';
    return $overrides;
}, 999 );

// Disable Gutenberg editor globally for all post types, terms, and widgets.
add_filter( 'use_block_editor_for_post', '__return_false', 100 );
add_filter( 'use_block_editor_for_post_type', '__return_false', 100 );
add_filter( 'use_block_editor_for_terms', '__return_false', 100 );
add_filter( 'use_block_editor_for_template', '__return_false', 100 );
add_filter( 'use_block_editor_for_navigation', '__return_false', 100 );
add_filter( 'use_widgets_block_editor', '__return_false', 100 );
add_filter( 'gutenberg_use_widgets_block_editor', '__return_false', 100 );
add_filter( 'should_load_separate_core_block_assets', '__return_false', 100 );
add_filter( 'wp_use_themes', '__return_false', 100 ); // Disable block-related theme processing.
add_filter( 'block_editor_rest_api_preload_paths', '__return_empty_array', 100 );
add_filter( 'should_load_theme_json', '__return_false', 100 );

// Prevent block editor from adding styles to post content.
remove_filter( 'the_content', 'do_blocks', 9 );

// Dequeue and deregister Gutenberg-related scripts and styles from both frontend and backend.
add_action( 'wp_enqueue_scripts', function() {
    // Dequeue Gutenberg-related styles and scripts on the frontend.
    wp_dequeue_style( 'wp-block-library' );         // WordPress core block styles.
    wp_dequeue_style( 'wp-block-library-theme' );   // WordPress core block theme styles.
    wp_dequeue_style( 'wp-edit-blocks' );           // Block editor styles (if applicable on the frontend).
    wp_dequeue_script( 'wp-block-editor' );         // Block editor script.
    wp_dequeue_script( 'wp-blocks' );               // Blocks script.
    wp_dequeue_script( 'wp-dom-ready' );            // DOM-ready script.

    // Deregister Gutenberg-related scripts on the frontend.
    wp_deregister_script( 'wp-block-editor' );      // Block editor script.
    wp_deregister_script( 'wp-blocks' );            // Block-related script.
    wp_deregister_script( 'wp-dom-ready' );         // DOM-ready script.

    // Remove inline styles and scripts related to the block editor.
    remove_action( 'wp_enqueue_scripts', 'wp_common_block_scripts_and_styles' ); // Block editor inline styles/scripts.
    remove_action( 'wp_head', 'wp_enqueue_editor_block_assets', 9 );  // Remove inline block editor styles.
}, 20 );

add_action( 'admin_enqueue_scripts', function() {
    // Dequeue Gutenberg-related styles and scripts on the backend.
    wp_dequeue_style( 'wp-block-library' );         // WordPress core block styles in admin.
    wp_dequeue_style( 'wp-block-library-theme' );   // WordPress core block theme styles in admin.
    wp_dequeue_style( 'wp-edit-blocks' );           // Block editor styles in admin.
    wp_dequeue_script( 'wp-block-editor' );         // Block editor script.
    wp_dequeue_script( 'wp-blocks' );               // Blocks script.
    wp_dequeue_script( 'wp-dom-ready' );            // DOM-ready script.

    // Deregister Gutenberg-related scripts in the admin area.
    wp_deregister_script( 'wp-block-editor' );      // Block editor script.
    wp_deregister_script( 'wp-blocks' );            // Block-related script.
    wp_deregister_script( 'wp-dom-ready' );         // DOM-ready script.
}, 20 );

// Conditionally disable WooCommerce block styles and scripts (if WooCommerce is installed).
if ( class_exists( 'WooCommerce' ) ) {
    add_action( 'wp_enqueue_scripts', function() {
        wp_dequeue_style( 'wc-block-style' );    // WooCommerce block styles (frontend).
        wp_dequeue_script( 'wc-blocks' );        // WooCommerce block scripts (frontend).
    }, 100 );

    // Disable WooCommerce block editor assets in the admin area.
    add_action( 'admin_enqueue_scripts', function() {
        wp_dequeue_style( 'wc-block-editor' );   // WooCommerce block editor styles (backend).
        wp_dequeue_script( 'wc-blocks-editor' ); // WooCommerce block editor scripts (backend).
    }, 100 );
}

// Prevent Gutenberg block editor scripts and styles from loading on post-editing pages.
add_action( 'enqueue_block_editor_assets', function() {
    wp_dequeue_script( 'wp-block-editor' );         // Dequeue block editor core scripts.
    wp_dequeue_style( 'wp-block-editor' );          // Dequeue block editor core styles.
    wp_dequeue_style( 'wp-edit-blocks' );           // Dequeue block editor block styles.
}, 100 );

// Disable block editor settings in Classic Widgets screen.
add_action( 'admin_enqueue_scripts', function() {
    if ( is_admin() && isset( $_GET['page'] ) && 'widgets.php' === $_GET['page'] ) {
        wp_dequeue_script( 'wp-block-editor' );  // Dequeue block editor scripts on the widgets screen.
        wp_dequeue_style( 'wp-edit-blocks' );    // Dequeue block editor styles on the widgets screen.
    }
}, 100 );

// Disable Gutenberg block editor in the media library.
add_action( 'wp_enqueue_media', function() {
    wp_dequeue_script( 'wp-block-editor' );  // Dequeue block editor scripts in media modals.
    wp_dequeue_style( 'wp-edit-blocks' );    // Dequeue block editor styles in media modals.
}, 100 );

// Disable REST API Gutenberg-related endpoints.
add_filter( 'rest_endpoints', function( $endpoints ) {
    // Remove block renderer endpoint.
    if ( isset( $endpoints['/wp/v2/block-renderer'] ) ) {
        unset( $endpoints['/wp/v2/block-renderer'] );
    }
    if ( isset( $endpoints['/wp/v2/wp_block'] ) ) {
        unset( $endpoints['/wp/v2/wp_block'] );
    }
    if ( isset( $endpoints['/wp/v2/global-styles'] ) ) {
        unset( $endpoints['/wp/v2/global-styles'] );
    }
    // Optionally remove other Gutenberg-related endpoints.
    if ( isset( $endpoints['/wp/v2/block-directory'] ) ) {
        unset( $endpoints['/wp/v2/block-directory'] );
    }
    if ( isset( $endpoints['/wp/v2/widgets'] ) ) {
        unset( $endpoints['/wp/v2/widgets'] );
    }
    if ( isset( $endpoints['/wp/v2/pattern-directory'] ) ) {
        unset( $endpoints['/wp/v2/pattern-directory'] );
    }
    
    return $endpoints;
}, 20 );

// Disable Gutenberg block editor settings globally in the backend.
add_filter( 'block_editor_settings_all', function( $settings ) {
    $settings['enableBlockDirectory']    = false;  // Disable block directory.
    $settings['disableCustomColors']     = true;   // Disable custom colors.
    $settings['disableCustomGradients']  = true;   // Disable custom gradients.
    $settings['disableCustomFontSizes']  = true;   // Disable custom font sizes.
    $settings['disableCustomLineHeight'] = true;   // Disable custom line heights.
    $settings['disableCustomUnits']      = true;   // Disable custom units.
    return $settings;
}, 20, 2 );

// Remove Gutenberg-specific nag notices or admin notices.
add_action( 'admin_menu', function() {
    remove_action( 'try_gutenberg_panel', 'wp_try_gutenberg_panel' );  // Remove Gutenberg try-out notice.
}, 10 );

// Disable Gutenberg-related actions during admin initialization.
add_action( 'admin_init', function() {
    remove_action( 'admin_init', 'gutenberg_add_post_type_templates' );  // Prevent post-type templates.
    remove_action( 'admin_init', 'gutenberg_add_widgets_block_editor' ); // Prevent widgets block editor.
}, 10 );

// Disable block editor settings in REST API JSON responses.
add_filter( 'block_editor_rest_api_post_dispatch', '__return_false', 10 );

// Disable Gutenberg in the Customizer.
add_action( 'customize_register', function() {
    remove_action( 'customize_controls_enqueue_scripts', 'wp_enqueue_block_editor_assets' );
}, 10 );

// Disable reusable blocks functionality.
add_action( 'init', function() {
    unregister_post_type( 'wp_block' );  // Reusable blocks post type.
}, 10 );

// Disable the block editor for widgets and enable the Classic Widgets interface.
add_filter( 'use_widgets_block_editor', '__return_false', 100 );

// Remove Gutenberg-related Site Health checks.
add_action( 'wp_site_health_scheduled_check', function() {
    remove_action( 'wp_site_health_scheduled_check', 'wp_block_editor_health_check', 10 );
}, 10 );

// Prevent block-based themes from enabling block editor functionality and disable theme.json support.
add_action( 'after_setup_theme', function() {
    remove_theme_support( 'block-editor' );
    remove_theme_support( 'block-template-parts' );  // For FSE (Full Site Editing) templates.
    remove_theme_support( 'block-templates' );       // Disable Full Site Editing templates.
    remove_theme_support( 'core-block-patterns' );   // Remove core block patterns.
    remove_theme_support( 'wp-block-styles' );       // Disable block-specific styles.
    remove_theme_support( 'widgets-block-editor' );
    remove_theme_support( 'block-align-wide' );     // Remove wide and full alignment options.
    remove_theme_support( 'editor-styles' );        // Disable editor styles in block editor.
    remove_theme_support( 'responsive-embeds' );    // Disable responsive embeds in block editor.
    remove_theme_support( 'editor-font-sizes' );    // Disable font size options in block editor.
    remove_theme_support( 'editor-color-palette' ); // Disable color options in block editor.
}, 10 );

// Disable block editor filters/actions in REST API requests.
add_action( 'rest_api_init', function() {
    add_filter( 'rest_prepare_block_template', '__return_null', 100 );  // Remove block template responses.
    add_filter( 'rest_preload_paths', '__return_empty_array', 100 );    // Prevent Gutenberg preloading.
    remove_action( 'rest_api_init', 'gutenberg_register_rest_routes' );  // Remove Gutenberg REST routes.

    // Add your new filter for REST API link curies.
    add_filter( 'rest_response_link_curies', function( $curies ) {
        return array_filter( $curies, function( $curie ) {
            return strpos( $curie['name'], 'wp-block' ) === false;
        } );
    }, 20 );
}, 20 );

// Disable block editor shortcodes.
add_action( 'init', function() {
    remove_shortcode( 'block' );
    remove_shortcode( 'wp-block' );
}, 20 );

// Remove all block categories.
add_filter( 'block_categories_all', function( $categories ) {
    return [];  // Return an empty array to remove all block categories.
}, 20, 1 );

// Unregister all core blocks.
add_action( 'init', function() {
    foreach ( WP_Block_Type_Registry::get_instance()->get_all_registered() as $block_type => $block ) {
        unregister_block_type( $block_type );  // Unregister all core blocks.
    }
}, 20 );

// Prevent block editor assets from preloading in REST API requests.
add_filter( 'rest_preload_paths', function( $preload_paths ) {
    return array_filter( $preload_paths, function( $path ) {
        return false === strpos( $path, '/wp/v2/block-editor' );
    } );
}, 20, 1 );

// Disable Gutenberg-specific admin notices and Global Styles interface.
add_action( 'admin_init', function() {
    remove_action( 'admin_notices', 'gutenberg_wordpress_version_notice' );  // Remove Gutenberg version notice.
    remove_action( 'admin_init', 'gutenberg_add_global_styles_panel' );      // Remove Global Styles panel.
}, 20 );

// Disable Gutenberg for Customizer Selective Refresh.
add_filter( 'customize_selective_refresh_block_editor', '__return_false', 10 );

// Ref: ChatGPT