Output hooked to the_content is output after template parts in Block Based Themes · Issue #20342 · WordPress/gutenberg · GitHub
How To Use the_content Function And Filter In WordPress [Guide] | Andriy Haydash
wordpress - the_excerpt and the_content filters - Stack Overflow
Using DOMDocument to add data attributes to images in Wordpress - Wp-starter - Wordpress services, tutorials and news
Joe Hall on Twitter: "add_filter('the_content','lazyIMG'); function lazyIMG($content) { $content = str_replace('<img','<img loading="lazy"', $content); return $content; }" / Twitter
Understanding the fundamentals of WordPress hooks | Assortment - For the practical developer
2. Hook into that action
The WordPress Hooks Bootcamp: How to Use Actions, Filters, and Custom Hooks - Atak Domain
How To Filter WordPress Content | NapitWPTech
WordPress: how to replace the output of the the_content() function with the post's excerpt | Gabriele Romanato
Wordpress Hooks Tutorial for beginners from scratch #16 Filter hook " the_content" - YouTube