Conflict with another plugin

Hello,

There appears to be a conflict between the product filter and another Plugin called Product Filter by WBW. When I run the filter in our product catalog, I get this error below the thumbnail of each listing:

Warning: call_user_func_array() expects parameter 1 to be a valid callback, class 'YITH_YWRAQ_Frontend' not found in [...]/wp-content/plugins/woo-product-filter/modules/woofilters/mod.php on line 2433

I’m not sure if this is an issue that needs to be fixed in the filter plugin or in YITH’s plugin, so I am informing both. It doesn’t appear to cause any problems with functionality, but it is displaying the message on the front end, so we would really appreciate a fix. Thanks.

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