Activating the plugin is breaking the website

Hi team,

If we activate the plugin the website breaks completely, and we can see the following error message:

Uncaught Error: Cannot use object of type WP_Error as array in /dom32110/wp-content/plugins/shortpixel-image-optimiser/class/db/wp-shortpixel-media-library-adapter.php on line 318
countAllProcessableFiles()
wp-content/plugins/shortpixel-image-optimiser/class/wp-short-pixel.php:3361
getQuotaInformation()
wp-content/plugins/shortpixel-image-optimiser/class/model/apikey_model.php:271
remoteValidate()
wp-content/plugins/shortpixel-image-optimiser/class/model/apikey_model.php:195
validateKey()
wp-content/plugins/shortpixel-image-optimiser/class/model/apikey_model.php:135
checkKey()
wp-content/plugins/shortpixel-image-optimiser/class/model/apikey_model.php:68
loadKey()
wp-content/plugins/shortpixel-image-optimiser/class/controller/apikey_controller.php:26
load()
wp-content/plugins/shortpixel-image-optimiser/class/wp-short-pixel.php:169
__construct()
wp-content/plugins/shortpixel-image-optimiser/wp-shortpixel.php:97
shortpixelInit()
/wordpress-5.2.4/wp-includes/class-wp-hook.php:286
apply_filters()
/wordpress-5.2.4/wp-includes/class-wp-hook.php:310
do_action()
/wordpress-5.2.4/wp-includes/plugin.php:465
do_action()
/wordpress-5.2.4/wp-settings.php:525
require_once()
wp-config.php:69
require_once()
wp-load.php:37
require_once()
/wordpress-5.2.4/wp-admin/admin.php:34
require_once()
/wordpress-5.2.4/wp-admin/plugins.php:10
The site is experiencing technical difficulties. Please check your site admin email inbox for instructions.

We’re trying to activate the version 4.14.6. And we do have the ‘SHORTPIXEL_API_KEY’ and SHORTPIXEL_HIDE_API_KEY’ set on wp-config.php
If we remove this from wp-config the plugin works again. This setting is not allowed anymore?

Yours,
Victor

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