Magento 2 - Best practice to modify third party extension

Question

I need to modify a template from a third party extension to match my current theme. In the extension layout xml file

app\code\IWD\Opc\view\frontend\layout\checkout_index_index.xml

<action method="setTemplate" ifconfig="iwd_opc/general/enable_in_frontend">
    <argument name="template" xsi:type="string">IWD_Opc::onepage.phtml</argument>
</action>

I can either change the template path in the layout xml file, or edit the onepage.phtml. But I don't want to change the original file. How to do it the right way?

Answer 1

Create a new storefront theme and put the file onepage.phtml in

app/design/frontend/[VendorName]/[theme]/IWD_Opc/templates/onepage.phtml

You can get more information from: http://devdocs.magento.com/guides/v2.0/frontend-dev-guide/themes/theme-inherit.html