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I am writing to you to report and at the same time try to resolve a problem I have on one of my client’s e-commerce sites. For some time we noticed a javascript error on the “checkout” page: Uncaught TypeError: e.addClass(…).block is not a function In the file: checkout.js:1:79255 In our opinion, this error prevents the possibility of dynamically changing the payment method. In fact, if you try to choose “payment on delivery” the extra fee requested by the site owner will not be added.

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