please review all-in-one/reverse-proxy.md at main · nextcloud/all-in-one · GitHub for reverse proxy setup instruction in AiO. from you logs it clear the CODE container can not access the URL https://cloud.varunpriolkar.com/apps/richdocuments/... and your browser can’t open WebSocket to wss://cloud.varunpriolkar.com/cool/
- Please double check networking inside of the container - how requests between CODE and Nextcloud are routed. review Collabora integration guide for implementation details..
- once https access works review if Websocket is enabled/allowed in the reverse proxy.