Disable the WordPress Editor Cleanup

disable_wordpress_editor_cleanup.php

/**
 * Disable the Visual and Text Editor p and br tag modifications when saving
 * 
 * When you call the editor, it will automatically add a filter depending
 * on which editor you have open:
 * * Text Editor: add_filter('the_editor_content', 'wp_htmledit_pre');
 * * Visual Editor: add_filter('the_editor_content', 'wp_richedit_pre');
 * 
 * The only way to stop this is to remove the filter because it's applied.
 * The next call after is do_action( 'media_buttons', $editor_id );
 * So to remove this, we want to add an action to the media_buttons
 * that removes the filters.
 * 
 * You can see which filters are loaded using: global $wp_filter;
 */
function skl_disable_wp_editor_formatting() {
    remove_filter('the_editor_content', 'wp_htmledit_pre');
    remove_filter('the_editor_content', 'wp_richedit_pre');
}
add_action( 'media_buttons', 'skl_disable_wp_editor_formatting');

/**
 * Disable the editor p and br tag modifications when switching
 * back and forth between the Visual and Text tabs
 */
function skl_disable_mce_cleanup(array $init) {
    $init = array_merge($init, array(
        'convert_fonts_to_spans' => false,
        'verify_html' => false,
        'fix_list_elements' => false,
        'forced_root_block' => false,
        'invalid_elements' => '',
        'invalid_styles' => '',
        'keep_styles' => true,
    ));
    
    return $init;
}
add_action( 'tiny_mce_before_init', 'skl_disable_mce_cleanup');