localstorage只存储一个对象，而不是添加连接它们

The idea of the below code is to add some product details to a localstorage variable everytime someone visits a product page with the goal to remember the last visited products. However, the variable only stores one product instead of adding them with "|" separators after each other. Hope someone can help out. The code seems legit.The idea of the below code is to add some produ