Customising the functionality of your WordPress site is often necessary to better align it with your goals. One way to do this is by editing a plugin’s code. While most plugins provide user-friendly settings, you may need to make specific modifications that are only possible by editing the code directly.
However, editing a WordPress plugin’s code requires caution. If done improperly, you can break your website, introduce security vulnerabilities, or lose your changes during plugin updates. In this blog, we’ll provide a step-by-step guide on how to safely edit a WordPress plugin’s code and protect your customisations.
Why You Might Need to Edit a WordPress Plugin’s Code?
There are several scenarios where editing a plugin’s code can be beneficial:
- Add Custom Features: Sometimes, a plugin doesn’t have the exact feature you need, and editing the code allows you to introduce that functionality.
- Modify Plugin Behaviour: You may need to change how a plugin operates or adjust certain settings that aren’t available through the WordPress dashboard.
- Fix Compatibility Issues: A plugin might conflict with your theme or other plugins, and a code edit can help resolve that issue.
- Remove Unnecessary Features: You might want to streamline a plugin by removing features that you don’t need, thus optimising your site’s performance.
While these reasons are valid, it’s important to follow best practices to avoid issues when modifying plugin code.
Learn about: Code Snippets in WordPress
Best Practices Before Editing Plugin Code
Before making any changes to a plugin’s code, always back up your website. Use a plugin like UpdraftPlus or BackWPup to create a full backup of your WordPress files and database.
- Use a Child Theme or Custom Functions Plugin: Instead of directly editing a plugin’s core files, consider using a child theme or a custom functions plugin. This allows you to add or modify functionality without touching the plugin’s source code.
- Avoid Direct Edits: Avoid directly editing the plugin’s main files whenever possible. Instead, use WordPress hooks, filters, or actions to add functionality.
- Understand the Code: If you’re unfamiliar with PHP, HTML, CSS, or JavaScript, study the code first or consult a developer. Editing code without understanding its function can lead to errors or site crashes.
Know about: White Label WordPress Development for Digital Agency
How to Edit WordPress Plugin Code: A Step-by-Step Guide
Before editing a live website, it’s highly recommended to create a staging environment. A staging site is a duplicate of your live website where you can test changes without affecting your real site. Many web hosts offer built-in staging environments, or you can use plugins like WP Staging to create one.
Step 1: Access the Plugin Files
There are two main ways to access and edit plugin files:
Via WordPress Admin (Theme/Plugin Editor)
From your WordPress dashboard, go to Appearance > Theme Editor or Plugins > Plugin Editor. Choose the plugin you want to edit from the drop-down menu and select the specific file you wish to modify.
Note: Be cautious when using this method, as incorrect edits could lead to your site breaking, and you won’t be able to undo changes easily.
Via FTP or File Manager
Use an FTP client (e.g., FileZilla) or your hosting provider’s File Manager to access your WordPress files. Navigate to the wp-content/plugins/
folder and find the plugin you want to edit. Download the file you wish to modify, make your changes locally, and upload the edited file back to the server.
Step 2: Locate the Code You Want to Edit
Once you’ve accessed the plugin files, you’ll need to locate the specific code you want to edit. Plugins are generally structured in multiple PHP, CSS, and JavaScript files, so you may need to spend some time finding the right file.
- If you’re modifying a visual element, you’ll likely be editing a CSS file.
- To change a functionality or behaviour, you’ll need to work within the PHP files.
- If you want to adjust dynamic interactions like pop-ups or animations, you might need to edit the JavaScript files.
Step 3: Make the Necessary Code Edits
Once you’ve found the correct file, it’s time to make your edits. Be sure to:
- Understand the code before making changes.
- Add comments to the code to explain what you’ve modified. This will help you (or others) remember what was changed if future edits are needed.
- Test the edits in your staging environment to make sure they work correctly and don’t introduce any new errors.
Example of editing a PHP file:
// Original code in the plugin's PHP file
function example_function() {
// Plugin functionality here
}
// Modified code with comments
function example_function() {
// Custom modification: added feature to change color
// Original functionality remains unchanged
echo '<style>body { background-color: #000; }</style>';
}
Step 4: Test the Changes
After making the changes, test your website on the staging site to ensure everything is working as expected. Check for:
- Broken layouts or CSS styles.
- PHP errors or warnings.
- Conflicts with other plugins or themes.
If everything works well, you can move the changes to your live site.
Also read: How to Create and Edit Pages in WordPress
Using WordPress Hooks and Filters Instead of Editing Code Directly
Whenever possible, it’s better to use WordPress hooks and filters to make changes, rather than editing plugin files directly. This method allows you to add custom functionality without modifying core plugin files, ensuring that your changes won’t be lost when the plugin updates.
What Are Hooks?
Hooks are functions that allow you to modify or add to the functionality of a plugin without touching its code. There are two types:
Actions: These hooks allow you to insert custom code at specific points during a WordPress page load or when certain events occur.
Filters: These hooks allow you to modify data before it is used by WordPress or a plugin.
Example of Using an Action Hook
Let’s say you want to add custom text to a WooCommerce checkout page. Instead of editing the plugin directly, you can use the woocommerce_before_checkout_form
action:
add_action( 'woocommerce_before_checkout_form', 'my_custom_text' );
function my_custom_text() {
echo '<p>Thank you for choosing us!</p>';
}
Example of Using a Filter Hook
If you want to modify the title of a product in WooCommerce, you can use a filter like this:
add_filter( 'the_title', 'custom_product_title' );
function custom_product_title( $title ) {
if ( is_product() ) {
$title = 'Custom Title: ' . $title;
}
return $title;
}
Read: Integrating Third-Party Services Into WordPress For Seamless Functionality
How to Protect Your Changes from Plugin Updates?
If you edit plugin code directly, any updates to the plugin will likely overwrite your changes. Here are a few ways to protect your modifications:
- Use a Custom Functions Plugin: Install a plugin like Code Snippets that allows you to add custom PHP functions without modifying plugin files. This keeps your changes safe during plugin updates.
- Child Themes for Theme-Dependent Plugins: If your plugin depends on your WordPress theme (e.g., theme-based plugins like Elementor), make changes in a child theme so they aren’t affected by updates.
- Use a Plugin Like WP Rollback: This plugin allows you to roll back to previous versions of a plugin if a new update overwrites your custom changes.
Find out: The Role Of WordPress In Web Development
Conclusion
Editing a WordPress plugin’s code can be a powerful way to customise your site’s functionality. However, always exercise caution by following best practices such as backing up your site, using a staging environment, and opting for hooks or filters when possible. By editing code responsibly, you can tailor plugins to meet your needs while minimising the risks associated with modifying core files.