I’m inserting a post using wp_post_insert(). And my post’s content looks like this:

<img src="data:image/png;base64, iVBORw0KGgoAAAANSUhEUgAAAN4AAAB6CA { ... }

but on the insert process, WordPress removes the data attribute. So below code becomes this:

 <img src="image/png;base64, iVBORw0KGgoAAAANSUhEUgAAAN4AAAB6CA { ... }

I’ve tried something like this but no luck:

function my_filter_allowed_html($allowed, $context){
if (is_array($context)) {
    return $allowed;
}

if ($context === 'post') {
    $allowed['img']['data'] = true;
    $allowed['src']['data'] = true;

}

return $allowed;
}
add_filter('wp_kses_allowed_html', 'my_filter_allowed_html', 10, 2);

How can I avoid this?