If you're trying to change the name of the Next button in the checkout shipping step in Magento and you're not seeing any changes after overriding the shipping.html file in your custom theme, there are a few things you can try:
Make sure that the file path for your custom shipping.html file is correct and that it's being loaded by your Magento installation. You can check this by navigating to your storefront and inspecting the source code to see if your custom file is being loaded.
Ensure that the HTML and JavaScript code for the Next button is correct and is not being overridden by another module or theme. You can use your browser's inspector tools to examine the code and see if there are any conflicts.
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