There is a bug in OpenCart 3.0.3.6 where the OCMOD modification is partially working or not working at all.
- To fix this issue, you need to access the file system/modification.xml
- Edit the file and copy-paste code as mentioned below or you can get the code from https://github.com/opencart/opencart/blob/3.0.x.x_Maintenance/upload/system/modification.xml
- After editing and saving the updated changes, click on Refresh Modification button on Admin: Extension > Modifications
<?xml version="1.0" encoding="utf-8"?>
<modification>
<name>Modification Default</name>
<code>default</code>
<version>1.1</version>
<author>OpenCart Ltd</author>
<link>http://www.opencart.com</link>
<file path="system/{engine,library}/{action,loader,config,language}*.php|system/library/template/template.php">
<operation>
<search regex="true">
<![CDATA[~(require|include)(_once)?\(([^)]+)~]]>
</search>
<add position="replace">
<![CDATA[$1$2(modification($3)]]>
</add>
</operation>
</file>
<file path="system/library/template/twig.php">
<operation>
<search>
<![CDATA[if (is_file($file)) {]]>
</search>
<add position="replace">
<![CDATA[if (defined('DIR_CATALOG') && is_file(DIR_MODIFICATION . 'admin/view/template/' . $filename . '.twig')) {
$code = file_get_contents(DIR_MODIFICATION . 'admin/view/template/' . $filename . '.twig');
} elseif (is_file(DIR_MODIFICATION . 'catalog/view/theme/' . $filename . '.twig')) {
$code = file_get_contents(DIR_MODIFICATION . 'catalog/view/theme/' . $filename . '.twig');
} elseif (is_file($file)) {]]>
</add>
</operation>
</file>
</modification>