Not working with PHP 7.2

Thanks for this simple but very helpful plug in.
But after updating to PHP 7.2 it doesn’t work anymore:

Warning: Parameter 2 to sbtonly_filter() expected to be a reference, value given in …./vampster.com/wp-includes/class-wp-hook.php on line 286

And after using the search there’s a blank screen.

Could you please fix it?

Thank you!
Markus

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