WordPress has notified of a problem

Hi Hummingbird people,

I installed your plugin a few days ago and have been very happy with it. But today I got an email from WordPress titled “Your Site is Experiencing a Technical Issue” and it nominated Hummingbird as the plugin that had caused the issue. It said the page causing the problem was /wp-admin/admin-ajax.php. The error message included in the email was (I have removed the parts of the URL that relate to my sitename):

Error Details
=============
An error of type E_ERROR was caused in line 84 of the file /wp-content/plugins/hummingbird-performance/core/class-core.php. Error message: Uncaught Error: Class ‘Hummingbird\Core\GDPR’ not found in /wp-content/plugins/hummingbird-performance/core/class-core.php:84
Stack trace:
#0 /wp-content/plugins/hummingbird-performance/core/class-core.php(64): Hummingbird\Core\Core->init()
#1 /wp-content/plugins/hummingbird-performance/wp-hummingbird.php(140): Hummingbird\Core\Core->__construct()
#2 /wp-content/plugins/hummingbird-performance/wp-hummingbird.php(129): Hummingbird\WP_Hummingbird->init()
#3 /wp-content/plugins/hummingbird-performance/wp-hummingbird.php(115): Hummingbird\WP_Hummingbird->__construct()
#4 /wp-includes/class-wp-hook.php(288): Hummingbird\WP_Hummingbird::get_instance(”)
#5 /wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters(NULL, Array)
#6 /wp-includes/plugin.php(478): WP_Hook->do_action(

Other details are:

WordPress version 5.3.2
Current theme: Arke Child (version 1.0.2)
Current plugin: Hummingbird (version 2.4.0)
PHP version 7.1.33

I haven’t noticed a problem so far (except an old plugin I use, BAW manual related posts has started misbehaving slightly, but I have no reason to think this is related), so maybe it was some temporary issue that my server was slow in loading something, I don’t know.

So I don’t have a problem, but the email suggested I contact you in case this information may be helpful to you.

Thanks.

The page I need help with: [log in to see the link]