How to Remove Core Meta Boxes/Panels in WordPress Post Edit Screen – Web/ Design/ Vista
How To Create Wordpress Meta Boxes — Smashing Magazine
Custom Field & Meta Box in Gutenberg Editor – Shellcreeper.com
add_meta_box() – Добавляет дополнительные блоки (meta box) на страницы редактирования/создания постов, постоянных страниц или произвольных типов записей в админ-панели.
Guide to Adding Custom Meta Boxes for Enhanced CMS
How to Add Custom Meta Box in WooCommerce Order Page?
php - How to Save Add meta box woocommerce wordpress - Stack Overflow
metabox - How to pass variable via $callback_args for add_meta_box - WordPress Development Stack Exchange
How to Add Post Meta Fields to Gutenberg Document Sidebar - A White Pixel
WordPress Meta Box Tutorials For Beginners Part # 1 | Register meta box to Post, Page & CPT - YouTube