How to remove/changes H3 Tags in Comments

Hi there,

this article explains:

https://docs.generatepress.com/article/generate_comments_title_output/

Where i add the code ?
tell me the where i add the code in a php file or the way,.

I've add the code on Snippet Plugin.
But not working

this is the screenshoot : https://prnt.sc/VH6882j3IXU0

I think we are not talking about the same thing, the filter you are using right now is targeting the h3 of 1 thought on your article, for h3 of the leave a comment, try this snippet, change h4 to p.
https://generatepress.com/forums/topic/change-comments-h-class-or-add-additional-css-to-exclude-in-table-of-content/#post-1149141