Server Management Server error

[Alex-Jongman]

I'm trying to setup a Visual Studio Code devcontainer that contains the community-server-connector.
After starting up the devcontainer, a message appears telling me that the server management server is running on port 9000 including a popup that states that port 9000 has been forwarded and is available.

But when I access that site I at localhost:9000 the browser shows nothing and in VSC I get the output:

Oct 23, 2024 12:55:04 PM org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer fireError
SEVERE: Missing header Content-Length in input "GET / HTTP/1.1
Host: localhost:9000
Connection: keep-alive
Cache-Control: max-age=0
sec-ch-ua: "Google Chrome";v="129", "Not=A?Brand";v="8", "Chromium";v="129"
sec-ch-ua-mobile: ?0
sec-ch-ua-platform: "Windows"
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Sec-Fetch-Site: none
Sec-Fetch-Mode: navigate
Sec-Fetch-User: ?1
Sec-Fetch-Dest: document
Accept-Encoding: gzip, deflate, br, zstd
Accept-Language: en-US,en;q=0.9,nl;q=0.8,de;q=0.7

"
java.lang.IllegalStateException: Missing header Content-Length in input "GET / HTTP/1.1
Host: localhost:9000
Connection: keep-alive
Cache-Control: max-age=0
sec-ch-ua: "Google Chrome";v="129", "Not=A?Brand";v="8", "Chromium";v="129"
sec-ch-ua-mobile: ?0
sec-ch-ua-platform: "Windows"
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Sec-Fetch-Site: none
Sec-Fetch-Mode: navigate
Sec-Fetch-User: ?1
Sec-Fetch-Dest: document
Accept-Encoding: gzip, deflate, br, zstd
Accept-Language: en-US,en;q=0.9,nl;q=0.8,de;q=0.7

"
	at org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.listen(StreamMessageProducer.java:91)
	at org.eclipse.lsp4j.jsonrpc.json.ConcurrentMessageProcessor.run(ConcurrentMessageProcessor.java:113)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:572)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
	at java.base/java.lang.Thread.run(Thread.java:1583)

I'm not sure if this error is an error due to a misconfigured devcontainer, but unfortunately information about setting up a dev environment is containing servers (tomcat & postgress server) in a devcontainer setting is very scarce.