"port" settings does not work

[homersimpsons]

1. Open launch.json
2. Write the following configuration

       {
           "name": "Listen for Xdebug",
           "type": "php",
           "request": "launch",
           "port": 9000
       },

3. Launch "Listen for Xdebug"
4. Launch "Listen for Xdebug" (a second time, without stopping the previous one)
5. Notice it fails with EADDRINUSE [...]::9003

OS Also reports listening on :9003

❯ ss -ltnp | grep -w ':9000'

❯ ss -ltnp | grep -w ':9003'
LISTEN 0      511                *:9003             *:*    users:(("code",pid=423773,fd=26))

Additional context:

• Extension Version 1.40.1
• VS Code version: 1.119.0
• OS: Ubuntu 24.04.4 LTS

Note that I'm trying to use this extension with Xdebug2, I can also confirm there that it is not connecting (note that 172.20.0.1 is my host ip from my docker container):

[100] Log opened at 2026-05-12 15:56:38
[100] I: Connecting to configured address/port: 172.20.0.1:9000.
[100] W: Creating socket for '172.20.0.1:9000', poll success, but error: Operation now in progress (29).
[100] E: Could not connect to client. :-(
[100] Log closed at 2026-05-12 15:56:38

But if I set xdebug.remote_port=9003 it "connects" (I have other issues after related to path mapping):

[100] Log opened at 2026-05-12 15:58:23
[100] I: Connecting to configured address/port: 172.20.0.1:9003.
[100] I: Connected to client. :-)

[zobo]

Strange indeed. Can you add "log":true to your launch.json configuration and see if there is anything useful on the Debug Console?

[homersimpsons]

Strange indeed. Can you add "log":true to your launch.json configuration and see if there is anything useful on the Debug Console?

It does not display anything on the first run, but does display the following on the second (broken) run (note that without "log": true it displays the same:

Error: listen EADDRINUSE: address already in use :::9003
    at Server.setupListenHandle [as _listen2] (node:net:1940:16)
    at listenInCluster (node:net:1997:12)
    at Server.listen (node:net:2102:7)
    at /home/homer/.vscode/extensions/xdebug.php-debug-1.40.1/out/phpDebug.js:336:24
    at new Promise (<anonymous>)
    at createServer (/home/homer/.vscode/extensions/xdebug.php-debug-1.40.1/out/phpDebug.js:267:36)
    at PhpDebugSession.launchRequest (/home/homer/.vscode/extensions/xdebug.php-debug-1.40.1/out/phpDebug.js:359:34)
    at PhpDebugSession.dispatchRequest (/home/homer/.vscode/extensions/xdebug.php-debug-1.40.1/node_modules/@vscode/debugadapter/lib/debugSession.js:385:22)
    at PhpDebugSession.dispatchRequest (/home/homer/.vscode/extensions/xdebug.php-debug-1.40.1/out/phpDebug.js:650:15)
    at PhpDebugSession.handleMessage (/home/homer/.vscode/extensions/xdebug.php-debug-1.40.1/node_modules/@vscode/debugadapter/lib/protocol.js:62:18) {
  code: 'EADDRINUSE',
  errno: -98,
  syscall: 'listen',
  address: '::',
  port: 9003
}

Note that:

1. In my opinion, the file is correctly saved as cating it from another terminal displays the correct content
2. Clicking on "Open 'launch.json'" effectively opens this file (under myproject/.vscode/launch.json)
3. When using remote_port it still does not seem to read the pathMappings so maybe there is an issue with the file loading on vscode end (I have no idea how to debug this), or maybe that is an issue only with xdebug2.
4. I was able to successfully start the debugger on another project (with default port: 9003 and pathMappings working) and setting "port": 9000 on this working project leads to the same issue.