Not Used and Not Shown Numeric fields produce error

Dear Forum,

This used to be fine with 4.0.1. Now with 4.1.1, we get errors for fields that are not shown (no checkbox in template) and not relevant to the end-user: xxx is not numeric.

*** PROBLEM wp-data-access ***
wp-content/plugins/wp-data-access/WPDataAccess/Simple_Form/WPDA_Simple_Form_Item.php
at bottom of file, line 962

// TENNIS BUG FIX: Noticed ” type = “string” and empty $this->item_value type = “NULL”, and as such,
// #20210128 the operator !== below tiggers incorrectly for empty fields. So changed it to !=
if ( ” != $this->item_value && ! is_numeric( $this->item_value ) ) {

Thanks for any help,
Tennis