Title: HTML Exception Error
Last modified: May 3, 2025
---
# HTML Exception Error
* Resolved [Websites Built For You](https://wordpress.org/support/users/websitesbuiltforyou/)
* (@websitesbuiltforyou)
* [11 months, 1 week ago](https://wordpress.org/support/topic/html-exception-error/)
* Just wanted to report a small issue I’ve had. Basically, the plugin was throwing
an error as below:
* [03-May-2025 08:16:36 UTC] PHP Fatal error: Uncaught ValueError: DOMDocument::
loadHTML(): Argument #1 ($source) must not be empty in /var/www/html/wp-content/
plugins/fix-alt-text/inc/Scan.php:532
Stack trace:#0 /var/www/html/wp-content/
plugins/fix-alt-text/inc/Scan.php(532): DOMDocument->loadHTML()#1 /var/www/html/
wp-content/plugins/fix-alt-text/inc/Scan.php(273): FixAltText\Scan::get_from_html()#
2 /var/www/html/wp-content/plugins/fix-alt-text/library/_helpers-library/inc/
Scan_Process_Library.php(779): FixAltText\Scan::scan_post()#3 /var/www/html/wp-
content/plugins/fix-alt-text/library/_helpers-library/inc/Scan_Process_Library.
php(462): FixAltText\HelpersLibrary\Scan_Process_Library->process()#4 /var/www/
html/wp-content/plugins/fix-alt-text/library/_helpers-library/inc/Scan_Process_Library.
php(1536): FixAltText\HelpersLibrary\Scan_Process_Library->handle()#5 /var/www/
html/wp-includes/class-wp-hook.php(324): FixAltText\HelpersLibrary\Scan_Process_Library-
>maybe_handle()#6 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->
apply_filters()#7 /var/www/html/wp-includes/plugin.php(517): WP_Hook->do_action()#
8 /var/www/html/wp-admin/admin-ajax.php(192): do_action()#9 {main} thrown in /
var/www/html/wp-content/plugins/fix-alt-text/inc/Scan.php on line 532
* This was causing the progress to get stuck. Turns out the issue was due to effectively
empty html (so for example ” ” (single space) not being detected on some post
types. I think this is because the site it’s installed on uses ACF extensively
and doesn’t always have main content.
I fixed it by adding a catch to the block
as below:
* public static function get_from_html( string $html, array $args = [] ): array{
* ```wp-block-code
// Must have something to scan
if ( empty( $args ) ) {
return [];
}
// Require HTML
if ( empty( $html ) ) {
return [];
}
// Empty array to hold all links to return
$all_references = [];
// Create DOM structure so we can reliably grab all img tags
$dom = new DOMDocument();
// Silence warnings
libxml_use_internal_errors( true );
// Ensure we are using UTF-8 Encoding
$html = htmlspecialchars_decode( htmlentities( $html, ENT_COMPAT, 'utf-8', false ) );
try {
// Load the URL's content into the DOM
$dom->loadHTML( $html, LIBXML_HTML_NODEFDTD | LIBXML_HTML_NOIMPLIED );
$images = $dom->getElementsByTagName( 'img' );
$image_index = 0;
// Ensure we have default values
$args['from_post_id'] = $args['from_post_id'] ?? 0;
$args['from_post_type'] = $args['from_post_type'] ?? '';
$args['from_where'] = $args['from_where'] ?? '';
$args['from_where_key'] = $args['from_where_key'] ?? '';
// Loop through each ![]()
tag in the dom and add it to the link array
foreach ( $images as $img ) {
// Inherit base details from args
$ref = $args;
// Fixing legacy code from breaking Gutenburg Editor
$img->removeAttribute( 'id' );
$ref['image_index'] = $image_index;
$ref['image_url'] = $img->getAttribute( 'src' );
$ref['image_alt_text'] = $img->getAttribute( 'alt' );
$all_references[] = new Reference( $ref );
++ $image_index;
}
} catch ( \Throwable $e ) {
error_log( print_r( $html, 1 ) );
// Deliberately empty.
}
// Done silencing errors
libxml_clear_errors();
//Return the links
return $all_references;
}
```
* Anyway, I know its not really a support issue but wanted to report it so you
could hopefully include in the next release of what is a great little plugin!
I’m going to leave a 5 star review for you now!
Thanks for all the hard work
guys!Steve
Viewing 4 replies - 1 through 4 (of 4 total)
* Plugin Author [Steven Ayers](https://wordpress.org/support/users/stevenayers63/)
* (@stevenayers63)
* [11 months, 1 week ago](https://wordpress.org/support/topic/html-exception-error/#post-18450452)
* [@websitesbuiltforyou](https://wordpress.org/support/users/websitesbuiltforyou/),
* Thank you for the bug report and fix! I will implement, test, and release something
later today. 🙂
* I’ll update this thread and close it once the new version has been released.
* -Steven
* Plugin Author [Steven Ayers](https://wordpress.org/support/users/stevenayers63/)
* (@stevenayers63)
* [11 months, 1 week ago](https://wordpress.org/support/topic/html-exception-error/#post-18451388)
* [@websitesbuiltforyou](https://wordpress.org/support/users/websitesbuiltforyou/),
* I just released version 1.9.1 to patch the bug you reported. Please update the
plugin and confirm that it solves the issue on your end.
* Once confirmed, I’ll close this support ticket.
* -Steven
* Plugin Author [Steven Ayers](https://wordpress.org/support/users/stevenayers63/)
* (@stevenayers63)
* [11 months, 1 week ago](https://wordpress.org/support/topic/html-exception-error/#post-18451419)
* [@websitesbuiltforyou](https://wordpress.org/support/users/websitesbuiltforyou/),
Also, this bug affected another plugin called [WhereUsed](https://wordpress.org/plugins/where-used/).
The fix will be released in version 1.5.0 of WhereUsed. Unfortunately, it will
take a little longer for that release as it is a big release.
* -Steven
* Thread Starter [Websites Built For You](https://wordpress.org/support/users/websitesbuiltforyou/)
* (@websitesbuiltforyou)
* [11 months ago](https://wordpress.org/support/topic/html-exception-error/#post-18459297)
* Hi Steven, sorry it took me a while but I can confirm that I’ve installed the
update and its working great.
Thanks again and keep up the great work!CheersSteve
Viewing 4 replies - 1 through 4 (of 4 total)
The topic ‘HTML Exception Error’ is closed to new replies.
* 
* [Fix Alt Text](https://wordpress.org/plugins/fix-alt-text/)
* [Support Threads](https://wordpress.org/support/plugin/fix-alt-text/)
* [Active Topics](https://wordpress.org/support/plugin/fix-alt-text/active/)
* [Unresolved Topics](https://wordpress.org/support/plugin/fix-alt-text/unresolved/)
* [Reviews](https://wordpress.org/support/plugin/fix-alt-text/reviews/)
* 4 replies
* 2 participants
* Last reply from: [Websites Built For You](https://wordpress.org/support/users/websitesbuiltforyou/)
* Last activity: [11 months ago](https://wordpress.org/support/topic/html-exception-error/#post-18459297)
* Status: resolved