Yes, I did. Followed the instruction in the manual all the way through and get the error below in seahub log:
2020-03-13 19:43:49,433 [ERROR] seahub.wopi.utils:102 get_wopi_dict HTTPSConnectionPool(host=‘collabora.xxxxxx.com’, port=443): Max retries exceeded with url: /hosting/discovery (Caused by SSLError(SSLError(“bad handshake: Error([(‘SSL routines’, ‘tls_process_server_certificate’, ‘certificate verify failed’)],)”,),))
I can view the xml file on collabora.xxxxxx.com and the site is using letsencrypt certificate.