remove seriesdropdown code from footer (not using dropdown)

Hey there,

first of all, I love this plugin. I’m having this for ages now.
Here and there I managed to add some features to it, but I cannot get my head around this issue.
The following code is inserted in every single page, but I want to have it removed, as I’m not using the dropdown options.

<script type=’text/javascript’><!–
var seriesdropdown = document.getElementById(“orgseries_dropdown”);
if (seriesdropdown) {
function onSeriesChange() {
if ( seriesdropdown.options[seriesdropdown.selectedIndex].value != ( 0 || -1 ) ) {
location.href = “https://utazgatok.hu/cikk-sorozat/”+seriesdropdown.options%5Bseriesdropdown.selectedIndex%5D.value;
}
}
seriesdropdown.onchange = onSeriesChange;
}
–></script>

The script is added by this line:
add_action( ‘wp_footer’, array($this, ‘series_dropdown_js’), 1 );

but I’m not sure, how to remove it, as it just prints out and not properly enqueues the script and also I don’t want to touch the plugin’s core file.

Thanks,
Andras