Nextcloud blank page and no client connecting

After the upgrade of Collabora Online – Built-in CODE Server to version 23.5.502, my nextcloud 27.1.2 installation ended up to a state in which connection via browser ended up to a white page followed by a timeout.

After a quick check to nextcloud.log in ./data/ folder, nextcloud itself complained by an error in View.php file caused by a wrong argument.

{"reqId":"$REQID","level":3,"time":"2023-09-16T13:57:25+00:00","remoteAddr":"$IP","user":"angie","app":"index","method":"POST","url":"/index.php/apps/richdocuments/wopi/files/153788_ocdf54wnrzrj/contents?access_token=Dq2ZP0lZ5x41FaGm51QIhltLi0cduzI1&access_token_ttl=$ACCESS_TOKEN_TTL%2Findex.php%2Fapps%2Frichdocuments%2Fwopi%2Ffiles%2F153788_ocdf54wnrzrj&compat=","message":"OC\\Files\\View::basicOperation(): Argument #2 ($path) must be of type string, null given, called in /var/www/sync/nextcloud/lib/private/Files/View.php on line 518 in file '/var/www/sync/nextcloud/lib/private/Files/View.php' line 1110","userAgent":"COOLWSD HTTP Agent 23.05.2.2","version":"27.0.2.1","exception":{"Exception":"Exception","Message":"OC\\Files\\View::basicOperation(): Argument #2 ($path) must be of type string, null given, called in /var/www/sync/nextcloud/lib/private/Files/View.php on line 518 in file '/var/www/sync/nextcloud/lib/private/Files/View.php' line 1110","Code":0,"Trace":[{"file":"/var/www/sync/nextcloud/lib/private/AppFramework/App.php","line":183,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/Route/Router.php","line":315,"function":"main","class":"OC\\AppFramework\\App","type":"::"},{"file":"/var/www/sync/nextcloud/lib/base.php","line":1071,"function":"match","class":"OC\\Route\\Router","type":"->"},{"file":"/var/www/sync/nextcloud/index.php","line":36,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/sync/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","Line":169,"Previous":{"Exception":"TypeError","Message":"OC\\Files\\View::basicOperation(): Argument #2 ($path) must be of type string, null given, called in /var/www/sync/nextcloud/lib/private/Files/View.php on line 518","Code":0,"Trace":[{"file":"/var/www/sync/nextcloud/lib/private/Files/View.php","line":518,"function":"basicOperation","class":"OC\\Files\\View","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/Files/Filesystem.php","line":545,"function":"file_exists","class":"OC\\Files\\View","type":"->"},{"file":"/var/www/sync/nextcloud/apps/files_versions/lib/Storage.php","line":189,"function":"file_exists","class":"OC\\Files\\Filesystem","type":"::"},{"file":"/var/www/sync/nextcloud/apps/files_versions/lib/Listener/FileEventsListener.php","line":210,"function":"store","class":"OCA\\Files_Versions\\Storage","type":"::"},{"file":"/var/www/sync/nextcloud/apps/files_versions/lib/Listener/FileEventsListener.php","line":107,"function":"write_hook","class":"OCA\\Files_Versions\\Listener\\FileEventsListener","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/EventDispatcher/ServiceEventListener.php","line":86,"function":"handle","class":"OCA\\Files_Versions\\Listener\\FileEventsListener","type":"->"},{"file":"/var/www/sync/nextcloud/3rdparty/symfony/event-dispatcher/EventDispatcher.php","line":251,"function":"__invoke","class":"OC\\EventDispatcher\\ServiceEventListener","type":"->"},{"file":"/var/www/sync/nextcloud/3rdparty/symfony/event-dispatcher/EventDispatcher.php","line":73,"function":"callListeners","class":"Symfony\\Component\\EventDispatcher\\EventDispatcher","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/EventDispatcher/EventDispatcher.php","line":94,"function":"dispatch","class":"Symfony\\Component\\EventDispatcher\\EventDispatcher","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/EventDispatcher/EventDispatcher.php","line":106,"function":"dispatch","class":"OC\\EventDispatcher\\EventDispatcher","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/Files/Node/HookConnector.php","line":112,"function":"dispatchTyped","class":"OC\\EventDispatcher\\EventDispatcher","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/legacy/OC_Hook.php","line":105,"function":"write","class":"OC\\Files\\Node\\HookConnector","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/Files/View.php","line":588,"function":"emit","class":"OC_Hook","type":"::"},{"file":"/var/www/sync/nextcloud/lib/private/Files/View.php","line":629,"function":"emit_file_hooks_pre","class":"OC\\Files\\View","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/Files/Node/File.php","line":73,"function":"file_put_contents","class":"OC\\Files\\View","type":"->"},{"file":"/var/www/sync/nextcloud/apps/richdocuments/lib/Controller/WopiController.php","line":504,"function":"putContent","class":"OC\\Files\\Node\\File","type":"->"},{"file":"/var/www/sync/nextcloud/apps/richdocuments/lib/Controller/WopiController.php","line":786,"function":"OCA\\Richdocuments\\Controller\\{closure}","class":"OCA\\Richdocuments\\Controller\\WopiController","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/sync/nextcloud/apps/richdocuments/lib/Controller/WopiController.php","line":763,"function":"retryOperation","class":"OCA\\Richdocuments\\Controller\\WopiController","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/Files/Lock/LockManager.php","line":29,"function":"OCA\\Richdocuments\\Controller\\{closure}","class":"OCA\\Richdocuments\\Controller\\WopiController","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/sync/nextcloud/apps/richdocuments/lib/Controller/WopiController.php","line":766,"function":"runInScope","class":"OC\\Files\\Lock\\LockManager","type":"->"},{"file":"/var/www/sync/nextcloud/apps/richdocuments/lib/Controller/WopiController.php","line":505,"function":"wrappedFilesystemOperation","class":"OCA\\Richdocuments\\Controller\\WopiController","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":230,"function":"putFile","class":"OCA\\Richdocuments\\Controller\\WopiController","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":137,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/AppFramework/App.php","line":183,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/sync/nextcloud/lib/private/Route/Router.php","line":315,"function":"main","class":"OC\\AppFramework\\App","type":"::"},{"file":"/var/www/sync/nextcloud/lib/base.php","line":1071,"function":"match","class":"OC\\Route\\Router","type":"->"},{"file":"/var/www/sync/nextcloud/index.php","line":36,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/sync/nextcloud/lib/private/Files/View.php","Line":1110},"CustomMessage":"--"}}

Just to regain access to the web configuration I disabled two apps (wich ended up in disabling Collabora Online – Built-in CODE Server)

On your installation you may probably call php intepreter via sudo with the correct user (eg www-data) which runs the webserver of nextcloud installation

$ occ app:disable richdocuments
$ occ app:disable richdocumentscode

After this you have to re-enable Collabora Online – Built-in CODE Server via the web interface. Given a couple of minutes to the CODE Server to start correctly, it will work again.

Hope it helps someone to save some time.