remove html comment tag

So I noticed that this line

<!– This page is cached by the Hummingbird Performance plugin v2.1.1 – https://wordpress.org/plugins/hummingbird-performance/. –>

appears at the very top of every page forcing !Doctype declaration to the right.

I used the following

add_filter(‘( $wphb_cache_config’,’__return_false’);

(found in class-page-cache.php line 1190)

Apparently it works but now I am not sure if this is the best way.

Another option would be to use

function callback($buffer) {

but this will slow website down significantly.

Any help appreciated. Thank you in advance.

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