Remove first image | CyberSEO Pro | Support Forum

need something like a edit post and remove first <p><img></p> after publish and set thumbnail. 
How I can do that? Where I can modify code for that? 

CyberSEO said
This article proposes a solution: https://www.cyberseo.net/blog/why-featured-images-appear-twice-in-cyberseo-posts-and-how-fix-it/  

It is not possible to hide featured image. I have custom theme =(
Maybe it has solution to edit post text after publish? I can write php code to remove first img tag (by regex), but I don't know where.

CyberSEO said
Yes, the plugin allows you to use custom PHP code to remove the first image tag from posts: https://www.cyberseo.net/content-syndicator/#php-code

The code should modify the $post['post_content'] variable.  

post_content doesn't have <img> tag...

  'post_content' => 'A recently identified malware named LOSTKEYS, which is capable of extracting files and system data.....'

But after posting in post it has 

<p><img class="aligncenter" src="https://website.com/wp-content/uploads/2025/05/russian-cyber-group-unveils-lostkeys-malware-in-recent-attacks-infosecurity-magazine.png" alt="Russian Cyber Group Unveils LOSTKEYS Malware in Recent Attacks - Infosecurity Magazine" /><br />A recently identified malware named LOSTKEYS.....