Astra Theme Customization Not Working

Astra Customizer Not Loading [Solved]

  • Published: December 1, 2024
  • Updated: April 26, 2025
  • 3 min read

The WordPress Customizer lets you adjust your website’s appearance in real time, but if you’re facing the Astra Customizer not loading issue, it can quickly turn a simple task into a frustrating experience.

Learn how I solved the Astra Theme customization issue with a simple code snippet. This article covers why the Astra Customizer sometimes fails to load, and how you can fix it.

One of my customers requested me to change his logo and a few images on his restaurant website. I quickly jumped in to WordPress dashboard and backed up the website before doing any changes.

A pretty simple task of changing the logo, turned out to be a slightly challenging task. Because the WordPress customizer wasn’t loading and Astra customizer settings or customizer preview not showing up.

Clearing the browser cache and server cache didn’t help. I was still seeing the blank screen below.

Astra Customizer Not Loading

Things I Checked First

At first, I thought it was due to a simple plugin conflict or a problematic plugin. So, I deactivated the suspected previously installed plugins. That didn’t help with the customizer issue.

So, I thought it was a inadequate WordPress memory or PHP environment variables issue.

Using Site Health widget on WordPress dashboard I checked the current WordPress and server environment variables. Configured them to ensure the Astra Theme system requirements are satisfied.

  • PHP version: 8.2 (Astra theme requires PHP 7.4 or greater)
  • WordPress memory: 1GB (Astra theme recommends 256 MB or higher, so you should check if the PHP memory limit is set to a minimum of 256M to prevent Customizer issues)
  • upload_max_filesize: 256M
  • post_max_size: 256M

How to Increase WordPress Memory Limit and Edit Other Variables

To increase WordPress memory limit using a plugin or your hosting provider control panel’s File Manager feature, navigate to the root folder of WordPress and edit wp-config.php

define( 'WP_MEMORY_LIMIT', '1024M' );

WordPress Memory Limit 1024MB

If you are using cPanel, go to PHP Selector or Multi PHP INI editor and click Options. You should be able to change certain environment variables depending on your hosting provider’s limitations. PHP options screen looks like this:

How to increase the PHP Max Upload Size in cPanel

Source of the Astra Customizer Not Loading Issue: Starter Templates

Astra Theme customizer still didn’t work even after I increased WordPress memory and the other PHP variables.

So, I kept digging and found out that if you are using Starter Templates along with Astra Theme, you needed to add following code snippet into .htaccess file (which is also found at the root WordPress folder)
<IfModule mod_substitute.c>
SubstituteMaxLineLength 10m
</IfModule>
This should fix the issue, allowing the customizer options to appear on your website.

Still Not Resolved?

The solution above should fix the Astra Customizer not working issue for most cases.

Here are the reasons that may cause WordPress customizer unable to load:

  • Check browser console for JavaScript errors using Chrome Dev Tools.
  • Clear your browser cache to remove any cache-related issues.
  • The blank screen in the Customizer area is a common issue due to resource exhaustion. Check the php error_log file. This file may contain signs of resource exhaustion or any other PHP compatibility error messages that may cause Customizer to malfunction.
  • If your WordPress Address (URL) and Site Address (URL) are not the same, it can cause issues with loading the Customizer preview correctly.
  • If the Customizer loads without styling, checking file permissions for CSS files. Usually file permissions should be 755. Contact your hosting provider to find out the correct file permissions.
  • Conflicts between plugins are a common cause for the WordPress Customizer not working. Deactivating all plugins temporarily one by one can help identify issues with the WordPress Customizer.
  • Deleting or making changes to invalid menu items can cause Customizer issues. Ensure that your menu items (pages) are valid.
  • If preview appears for a moment and then customizer stops working, your WordPress customizer settings might contain corrupted field values. Try using Reset Customizer plugin to reset the Customizer if issue persists.
  • If your server is running an outdated PHP version (7.2 or earlier), it can cause HTTP 500 Internal Server Error. To fix this, you will need to update your PHP version to a newer version, preferably 8.2 or later.
  • If none of the solutions work, consider getting expert developer help from an experienced WordPress Expert.

Related Posts