Apache configuration
nc.mynextcloud.com.conf
<IfModule mod_ssl.c>
<VirtualHost *:443>
        # The ServerName directive sets the request scheme, hostname and port that
        # the server uses to identify itself. This is used when creating
        # redirection URLs. In the context of virtual hosts, the ServerName
        # specifies what hostname must appear in the request's Host: header to
        # match this virtual host. For the default virtual host (this file) this
        # value is not decisive as it is used as a last resort host regardless.
        # However, you must set it for any further virtual host explicitly.
        ServerName nc.mynextcloud.com
        ServerAlias nc.mynextcloud.com
        SSLEngine on

        ServerAdmin info@mynextcloud.com
        DocumentRoot /var/www/nextcloud

        # Available loglevels: trace8, ..., trace1, debug, info, notice, warn,
        # error, crit, alert, emerg.
        # It is also possible to configure the loglevel for particular
        # modules, e.g.
        #LogLevel info ssl:warn

        ErrorLog ${APACHE_LOG_DIR}/error.log
        CustomLog ${APACHE_LOG_DIR}/access.log combined

        # For most configuration files from conf-available/, which are
        # enabled or disabled at a global level, it is possible to
        # include a line for only one particular virtual host. For example the
        # following line enables the CGI configuration for this host only
        # after it has been globally disabled with "a2disconf".
        #Include conf-available/serve-cgi-bin.conf
    <IfModule mod_headers.c>
      Header always set Strict-Transport-Security "max-age=15552000; includeSubDomains"
    </IfModule>

Include /etc/letsencrypt/options-ssl-apache.conf
SSLCertificateFile /etc/letsencrypt/live/nc.mynextcloud.com-0001/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/nc.mynextcloud.com-0001/privkey.pem
</VirtualHost>
</IfModule>

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office.mynextcloud.com-le-ssl.conf
<IfModule mod_ssl.c>
<VirtualHost *:443>
 ServerName office.mynextcloud.com:443
 ServerAlias office.mynextcloud.com
 AllowEncodedSlashes NoDecode
 ProxyPreserveHost On


 # static html, js, images, etc. served from coolwsd
 # browser is the client part of Collabora Online
 ProxyPass           /browser http://127.0.0.1:9980/browser retry=0
 ProxyPassReverse    /browser http://127.0.0.1:9980/browser


 # WOPI discovery URL
 ProxyPass           /hosting/discovery http://127.0.0.1:9980/hosting/discovery retry=0
 ProxyPassReverse    /hosting/discovery http://127.0.0.1:9980/hosting/discovery


 # Capabilities
 ProxyPass           /hosting/capabilities http://127.0.0.1:9980/hosting/capabilities retry=0
 ProxyPassReverse    /hosting/capabilities http://127.0.0.1:9980/hosting/capabilities


 # Main websocket
 ProxyPassMatch      "/cool/(.*)/ws$"      ws://127.0.0.1:9980/cool/$1/ws nocanon


 # Admin Console websocket
 ProxyPass           /cool/adminws ws://127.0.0.1:9980/cool/adminws


 # Download as, Fullscreen presentation and Image upload operations
 ProxyPass           /cool http://127.0.0.1:9980/cool
 ProxyPassReverse    /cool http://127.0.0.1:9980/cool
 # Compatibility with integrations that use the /lool/convert-to endpoint
 ProxyPass           /lool http://127.0.0.1:9980/cool
 ProxyPassReverse    /lool http://127.0.0.1:9980/cool

Include /etc/letsencrypt/options-ssl-apache.conf
SSLCertificateFile /etc/letsencrypt/live/office.mynextcloud.com/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/office.mynextcloud.com/privkey.pem
</VirtualHost>
</IfModule>