sub formatText {
    my ($node, $target, $tag) = @_;
    my @children = $node->detach_content ();
    my @newChildren;
    
    for (@children) {
        if (ref) {
            formatText ($_, $target, $tag);
            push @newChildren, $_;
            next;
        }
        
        my @fragments = split /($target)/, $_;
        
        while (@fragments) {
            push @newChildren, shift @fragments;
            
            last if ! @fragments;
            my $element = HTML::Element->new ($tag);
            $element->push_content (shift @fragments);
            push @newChildren, $element;
        }
    }

    $node->push_content (@newChildren) if @newChildren;
}