I’ve discovered that the problem is caused by the Axepta BNP Paribas plugin, but contacting their support is troublesome. Is there an easy and non-conflicting way to detach the reorder_available_payment_gateways function from the woocommerce_available_payment_gateways filter or overwrite it so it simply looks like this?
public function reorder_available_payment_gateways( $gateways ){
return $gateways
}
I just checked and the error also occurs when enabling another theme, TT4.