This is the system error email when enabled Authorizer and Collaboration. Thank you.
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When seeking help with this issue, you may be asked for some of the following information:
WordPress version 5.8
Current theme: Twenty Twenty-One (version 1.4) Current plugin: Aether – dPlugins Framework (version 1.1.17) PHP version 7.4.3
Error Details
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An error of type E_ERROR was caused in line 61 of the file /var/www/emhk/wp-content/plugins/aether/vendor/guzzlehttp/guzzle/src/functions.php. Error message: Uncaught Error: Call to undefined method GuzzleHttp\Utils::chooseHandler() in /var/www/emhk/wp-content/plugins/aether/vendor/guzzlehttp/guzzle/src/functions.php:61
Stack trace:
#0 /var/www/emhk/wp-content/plugins/authorizer/vendor/guzzlehttp/guzzle/src/HandlerStack.php(42): GuzzleHttp\choose_handler()
#1 /var/www/emhk/wp-content/plugins/authorizer/vendor/guzzlehttp/guzzle/src/Client.php(65): GuzzleHttp\HandlerStack::create()
#2 /var/www/emhk/wp-content/plugins/oxyrealm-collaboration/vendor/pusher/pusher-php-server/src/Pusher.php(69): GuzzleHttp\Client->__construct()
#3 /var/www/emhk/wp-content/plugins/oxyrealm-collaboration/oxyrealm-collaboration.php(142): Pusher\Pusher->__construct()
#4 /var/www/emhk/wp-includes/class-wp-hook.php(303): Oxyrealm\Modules\Collaboration\Collaboration->boot()
#5 /var/www/emhk/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters()
#6 /var/www/emhk/wp-includes/plugin.php(470): WP_Hook->do_action()
#7 /var/www/emhk/wp-settings.php(578): do_action()
#8 /var/www/emhk/w`