Over night I received an email from my website that it has gone down, while nothing actually happened (auto updates are disabled). Investigation led to the dPlugins Collaboration plugin, which threw the following error:
Uncaught Error: Call to undefined method GuzzleHttpUtils::chooseHandler() in /home/example/domains/example.com/public_html/wp-content/plugins/dplugins-collaboration/vendor/guzzlehttp/guzzle/src/functions.php:61 Stack trace: #0 /home/example/domains/example.com/public_html/wp-content/plugins/wp-seopress/vendor/guzzlehttp/guzzle/src/HandlerStack.php(42): GuzzleHttpchoose_handler() #1 /home/example/domains/example.com/public_html/wp-content/plugins/wp-seopress/vendor/guzzlehttp/guzzle/src/Client.php(65): GuzzleHttpHandlerStack::create() #2 /home/example/domains/example.com/public_html/wp-content/plugins/dplugins-collaboration/vendor/pusher/pusher-php-server/src/Pusher.php(69): GuzzleHttpClient->__construct() #3 /home/example/domains/example.com/public_html/wp-content/plugins/dplugins-collaboration/src/Collaboration.php(125): PusherPusher->__construct('7dee46b5d39792b...', '6ec60acb5beaece...', '1211590', Array)
Nothing changed at all on the website or the server, but still it went down for no reason. It also looks like SEOPress had something to do with it (using incompatible Guzzle versions maybe?). Could you please let me know how this could have happened? The problem is currently fixed by disabling the Collaboration plugin.
WordPress version 5.8.3 Current thema: blank-theme-2 Current plugin: dPlugins Collaboration (version 1.2.0) PHP version 7.4.26