Sorry, I didn’t look close enough.
After following your steps, Collabora_Online.AppImage is running and listening:
...
Ready to accept connections on port 9983
But… Nextcloud office is still not working. Opening a document takes about 20 seconds and results in an error as before:
Document loading failed
Failed to load Nextcloud Office - please try again later
Once again, I checked the settings. Nothing unusual, at least for me.
Multiple log errors like this one:
{"reqId":"yPtF9pjR87ae11z4hdUu","level":3,"time":"2025-07-04T07:24:40+00:00","remoteAddr":"2003:f6:170a:1000:1ce9:eca:2793:65f2","user":"MYUSER","app":"richdocuments","method":"GET","url":"/nextcloud/core/preview?fileId=426452&x=250&y=250","message":"Failed to convert preview: Client error: `POST https://MYDOMAIN.TLD/nextcloud/apps/richdocumentscode/proxy.php?req=/cool/convert-to/png` resulted in a `400 Bad Request` response:\n<html><body>\n<h1>Socket proxy error</h1>\n<p>Error: No content in reply from coolwsd. Is SSL enabled in error ?</p>\n</bod (truncated...)\n","userAgent":"Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.0","version":"31.0.6.2","exception":{"Exception":"GuzzleHttp\\Exception\\ClientException","Message":"Client error: `POST https://MYDOMAIN.TLD/nextcloud/apps/richdocumentscode/proxy.php?req=/cool/convert-to/png` resulted in a `400 Bad Request` response:\n<html><body>\n<h1>Socket proxy error</h1>\n<p>Error: No content in reply from coolwsd. Is SSL enabled in error ?</p>\n</bod (truncated...)\n","Code":400,"Trace":[{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/guzzle/src/Middleware.php","line":72,"function":"create","class":"GuzzleHttp\\Exception\\RequestException","type":"::","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":209,"function":"GuzzleHttp\\{closure}","class":"GuzzleHttp\\Middleware","type":"::","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":158,"function":"callHandler","class":"GuzzleHttp\\Promise\\Promise","type":"::"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/TaskQueue.php","line":52,"function":"GuzzleHttp\\Promise\\{closure}","class":"GuzzleHttp\\Promise\\Promise","type":"::","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":251,"function":"run","class":"GuzzleHttp\\Promise\\TaskQueue","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":227,"function":"invokeWaitFn","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":272,"function":"waitIfPending","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":229,"function":"invokeWaitList","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":69,"function":"waitIfPending","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/guzzle/src/Client.php","line":189,"function":"wait","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/lib/private/Http/Client/Client.php","line":277,"function":"request","class":"GuzzleHttp\\Client","type":"->"},{"file":"/var/www/nextcloud/apps/richdocuments/lib/Service/RemoteService.php","line":87,"function":"post","class":"OC\\Http\\Client\\Client","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/nextcloud/apps/richdocuments/lib/Service/RemoteService.php","line":67,"function":"convertTo","class":"OCA\\Richdocuments\\Service\\RemoteService","type":"->"},{"file":"/var/www/nextcloud/apps/richdocuments/lib/Preview/Office.php","line":41,"function":"convertFileTo","class":"OCA\\Richdocuments\\Service\\RemoteService","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/GeneratorHelper.php","line":44,"function":"getThumbnail","class":"OCA\\Richdocuments\\Preview\\Office","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":342,"function":"getThumbnail","class":"OC\\Preview\\GeneratorHelper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":313,"function":"generateProviderPreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":117,"function":"getMaxPreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":87,"function":"generatePreviews","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/PreviewManager.php","line":161,"function":"getPreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/core/Controller/PreviewController.php","line":168,"function":"getPreview","class":"OC\\PreviewManager","type":"->"},{"file":"/var/www/nextcloud/core/Controller/PreviewController.php","line":127,"function":"fetchPreview","class":"OC\\Core\\Controller\\PreviewController","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":200,"function":"getPreviewByFileId","class":"OC\\Core\\Controller\\PreviewController","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":114,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/App.php","line":161,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/Route/Router.php","line":307,"function":"main","class":"OC\\AppFramework\\App","type":"::"},{"file":"/var/www/nextcloud/lib/base.php","line":1040,"function":"match","class":"OC\\Route\\Router","type":"->"},{"file":"/var/www/nextcloud/index.php","line":24,"function":"handleRequest","class":"OC","type":"::"}],"File":"/var/www/nextcloud/3rdparty/guzzlehttp/guzzle/src/Exception/RequestException.php","Line":111,"message":"Failed to convert preview: Client error: `POST https://MYDOMAIN.TLD/nextcloud/apps/richdocumentscode/proxy.php?req=/cool/convert-to/png` resulted in a `400 Bad Request` response:\n<html><body>\n<h1>Socket proxy error</h1>\n<p>Error: No content in reply from coolwsd. Is SSL enabled in error ?</p>\n</bod (truncated...)\n","exception":[],"CustomMessage":"Failed to convert preview: Client error: `POST https://MYDOMAIN.TLD/nextcloud/apps/richdocumentscode/proxy.php?req=/cool/convert-to/png` resulted in a `400 Bad Request` response:\n<html><body>\n<h1>Socket proxy error</h1>\n<p>Error: No content in reply from coolwsd. Is SSL enabled in error ?</p>\n</bod (truncated...)\n"},"id":"6867823a1adb2"}