Change H2 to H6 in Post Content Widget

Hello, here’s what I’m trying to do as well as what I’ve already done:

I want to change all the titles in my widgets from H2 to H6. I’ve successfully done that to my sidebars by adding this code into my functions:

if ( function_exists( ‘register_sidebars’ ) )
register_sidebar( array(
‘name’ => __( ‘Sidebar’ ),
‘before_widget’ => ‘<div id=”%1$s” class=”widget %2$s”>’,
‘after_widget’ => ‘</div>’,
‘before_title’ => ‘<h6 class=”widgettitle”>’,
‘after_title’ => ‘</h6>’
) );

This works great for the sidebar. Here’s the catch I’m having problems with.

I’ve incorporated the jetpack subscriptions widget right below my content area (kind of in the content area). The jetpack subscription widget has a title tag of h2. I want to change this to H6. With the above code it’s registering the sidebar, how do I get it to also register the post content?

I’ve hidden the jetpack subscriptions element with CSS, however that just hides it from the human eye. The H2 code still shows up when SEO is concerned.

Site URL: https://appducate.com

I’d really appreciate your assistance. Thank you.