Blur and cross out stopped working

Hi,

The function “blur and cross out” doesn’t seem to work on our website anymore.
I installed a “waiting list” plugin for people to subsribe for a product to get an email when it will be back in stock and then it broke the “blur and cross out”.
But even after deativating and deleting it from our website the “blur and cross out” doesnt work anymore.

This is an example products of which most items are sold out:
https://fosamsterdam.nl/product/nico-6427-600-lurex-rood

I hope you can help.

Best regards
Olga

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