WP 5.0 Gutenberg breaks page builder

The latest WordPress update added a new page builder called Gutenberg. Unfortunately, this builder is not compatible with Hybrid Composer. Until theme updates are uploaded to Themeforest, follow these steps to disable Gutenberg:

• install and activate child theme
• go to Appearance - Editor, choose functions.php from the right panel
• add this line anywhere at the end of the file

add_filter('use_block_editor_for_post', '__return_false');