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WordPress WordPress Hooks - Actions and Filters An Overview of Hooks in WordPress Working with $wp_filter

Shaun Glassman
Shaun Glassman
6,496 Points

Getting an "Uncaught TypeError: Cannot read property 'className' of null -- Page is working but what is with this error?

I'm getting a strange error in the console when I run the page. The site runs as expected (I previously think I had some weird caching issues) but with the following error:

Uncaught TypeError: Cannot read property 'className' of null

If I follow where they say the problem is, it's on like 57 of this piece of code: <script type="text/javascript"> (function() { var request, b = document.body, c = 'className', cs = 'customize-support', rcs = new RegExp('(^|\s+)(no-)?'+cs+'(\s+|$)');

        request = true;

        b[c] = b[c].replace( rcs, ' ' );   //This is line 57
        b[c] += ( window.postMessage && request ? ' ' : ' no-' ) + cs;

My functions file is: <?php require_once('examples/export_wp_filter.php'); ?>

My export_wp_filter.php file is as downloaded from the site: <pre> <?php var_export( $wp_filter ); ?> </pre>

The index page is also default: <title><?php wp_title( '|', true, 'right' ); ?></title>

<?php wp_head(); ?>

<?php wp_footer(); ?>

What could be causing this error and could this be problematic in the future?

HI Shaun,

Change your index.php to :

<title><?php wp_title( '|', true, 'right' ); ?></title>

<?php get_header(); ?>

<?php get_footer(); ?>