WordPress at a glance
filter is not described

comment_edit_pre filter-hook . WP 2.0.0

Filters the comment content before editing.

Usage

add_filter( 'comment_edit_pre', 'filter_function_name_7434' );
function filter_function_name_7434( $comment_content ){
	// filter...

	return $comment_content;
}
$comment_content(string)
Comment content.

Where the hook is called

get_comment_to_edit()
comment_edit_pre
WP_Comments_List_Table::column_comment()
comment_edit_pre
wp-admin/includes/comment.php 111
$comment->comment_content = apply_filters( 'comment_edit_pre', $comment->comment_content );
wp-admin/includes/class-wp-comments-list-table.php 664
echo esc_textarea( apply_filters( 'comment_edit_pre', $comment->comment_content ) );

Where the hook is used (in WP core)

Does not used.