web: fix setting prefix for subdomains

web/rootfs/defaults/meet.conf

@@ -22,6 +22,8 @@ error_page 404 /static/404.html;
 add_header X-Content-Type-Options nosniff;
 add_header X-XSS-Protection "1; mode=block";
 
+set $prefix "";
+
 {{ if .Env.DEPLOYMENTINFO_SHARD }}
 add_header X-Jitsi-Shard {{ .Env.DEPLOYMENTINFO_SHARD }};
 {{ end }}
@@ -79,7 +81,7 @@ location = /http-bind {
     proxy_set_header X-Forwarded-For $remote_addr;
     proxy_set_header Host {{ $XMPP_DOMAIN }};
 
-    proxy_pass {{ $XMPP_BOSH_URL_BASE }}/http-bind;
+    proxy_pass {{ $XMPP_BOSH_URL_BASE }}/http-bind?prefix=$prefix&$args;
 }
 
 {{ if $ENABLE_XMPP_WEBSOCKET }}
@@ -93,7 +95,7 @@ location = /xmpp-websocket {
     proxy_set_header Host {{ $XMPP_DOMAIN }};
     proxy_set_header X-Forwarded-For $remote_addr;
 
-    proxy_pass {{ $XMPP_BOSH_URL_BASE }}/xmpp-websocket;
+    proxy_pass {{ $XMPP_BOSH_URL_BASE }}/xmpp-websocket?prefix=$prefix&$args;
 }
 {{ end }}