Order email custom fields always end with comma like in the screenshot below:
We need to get rid of that in the end. Could you please help us get it fix?
In this case, could you please replace this file: app/code/Bss/CheckoutCustomField/Helper/Data.php by the attachment to fix your issue with comma?
After that, please clear cache and test sending the email again.
For more information about product, please refer Checkout Custom Field for Magento 2.
If you need any further assistance, please feel free to contact us.
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