diff --git a/CHANGELOG.md b/CHANGELOG.md
index 769cc853..119ddfdf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,9 @@
 
 ## v3.2.0
 
-...
+### Features
+
+* Builtin Prosody: new settings to enable local C2S. For example, can be used with Matterbridge (thanks https://github.com/tytan652)
 
 ## v3.1.0
 
diff --git a/ROADMAP.md b/ROADMAP.md
index 8820d081..68241fbb 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -36,3 +36,4 @@ This roadmap is given as an indication. It will be updated as we go along accord
 [ ] | Builtin Prosody | Add a settings to enable the server to be accessed with XMPP clients.
 [ ] | ConverseJS | For anonymous user, automatically log in with a random nickname (and allow to change afterward)
 [ ] | Common | There should be a settings to add terms & conditions in the Peertube's about page (for example if the webchat is hosted anywhere else).
+[ ] | Builtin Prosody | Add on option to limit webchat to registered users.
diff --git a/client/admin-plugin-client-plugin.ts b/client/admin-plugin-client-plugin.ts
index 942fdffb..73787348 100644
--- a/client/admin-plugin-client-plugin.ts
+++ b/client/admin-plugin-client-plugin.ts
@@ -114,7 +114,14 @@ function register ({ registerHook, registerSettingsScript, peertubeHelpers }: Re
         case 'prosody-peertube-uri':
         case 'chat-type-help-builtin-prosody':
         case 'prosody-list-rooms':
+        case 'prosody-advanced':
+        case 'prosody-c2s':
           return options.formValues['chat-type'] !== ('builtin-prosody' as ChatType)
+        case 'prosody-c2s-port':
+          return !(
+            options.formValues['chat-type'] === ('builtin-prosody' as ChatType) &&
+            options.formValues['prosody-c2s'] === true
+          )
         case 'chat-server':
         case 'chat-room':
         case 'chat-bosh-uri':
diff --git a/documentation/prosody.md b/documentation/prosody.md
index b6433950..e7aaed4e 100644
--- a/documentation/prosody.md
+++ b/documentation/prosody.md
@@ -61,6 +61,21 @@ This is the port that the Prosody server will use. By default it is set to 52800
 These settings are common with other chat modes.
 Here is the documentation: [common settings](./common.md).
 
+### Prosody advanced settings
+
+#### Enable client to server connections
+
+This setting enable XMPP clients to connect to the builtin Prosody server.
+For now, this option **only allows connections from localhost clients**.
+
+As example, this option can allow an instance of Matterbridge (once it could use anonymous login) *on the same machine* to bridge your chat with another services like a Matrix room.
+
+##### Prosody client to server port
+
+The port that will be used by the c2s module of the builtin Prosody server.
+XMPP clients shall use this port to connect.
+Change it if this port is already in use on your server.
+
 ## Moderation
 
 You can list all existing chatrooms: in the plugin settings screen, there is a button «List rooms».
diff --git a/server/lib/prosody/config.ts b/server/lib/prosody/config.ts
index 85e3e7f0..1c077845 100644
--- a/server/lib/prosody/config.ts
+++ b/server/lib/prosody/config.ts
@@ -77,6 +77,7 @@ async function getProsodyConfig (options: RegisterServerOptions): Promise<Prosod
   if (!/^\d+$/.test(port)) {
     throw new Error('Invalid port')
   }
+  const enableC2s = (await options.settingsManager.getSetting('prosody-c2s') as boolean) || false
   const prosodyDomain = await getProsodyDomain(options)
   const paths = await getProsodyFilePaths(options)
 
@@ -99,6 +100,14 @@ async function getProsodyConfig (options: RegisterServerOptions): Promise<Prosod
   config.usePeertubeBosh(prosodyDomain, port)
   config.useMucHttpDefault(roomApiUrl)
 
+  if (enableC2s) {
+    const c2sPort = (await options.settingsManager.getSetting('prosody-c2s-port') as string) || '52822'
+    if (!/^\d+$/.test(c2sPort)) {
+      throw new Error('Invalid c2s port')
+    }
+    config.useC2S(c2sPort)
+  }
+
   // TODO: add a settings so that admin can choose? (on/off and duration)
   config.useMam('1w') // Remove archived messages after 1 week
   // TODO: add a settings to choose?
diff --git a/server/lib/prosody/config/content.ts b/server/lib/prosody/config/content.ts
index 43ec98de..6fb0f107 100644
--- a/server/lib/prosody/config/content.ts
+++ b/server/lib/prosody/config/content.ts
@@ -203,6 +203,10 @@ class ProsodyConfigContent {
     }
   }
 
+  useC2S (c2sPort: string): void {
+    this.global.set('c2s_ports', [c2sPort])
+  }
+
   useMucHttpDefault (url: string): void {
     this.muc.add('modules_enabled', 'muc_http_defaults')
     this.muc.add('muc_create_api_url', url)
diff --git a/server/lib/settings.ts b/server/lib/settings.ts
index a1462617..23e29ac0 100644
--- a/server/lib/settings.ts
+++ b/server/lib/settings.ts
@@ -276,6 +276,38 @@ Example: height:400px;`,
     private: false
   })
 
+  // ********** Built-in Prosody advanced settings
+  registerSetting({
+    name: 'prosody-advanced',
+    type: 'html',
+    private: true,
+    descriptionHTML: '<h3>Prosody advanced settings</h3>'
+  })
+
+  registerSetting({
+    name: 'prosody-c2s',
+    label: 'Enable client to server connections',
+    type: 'input-checkbox',
+    default: false,
+    private: true,
+    descriptionHTML:
+`Enable XMPP clients to connect to the builtin Prosody server.<br>
+This option alone only allows connections from localhost clients.`
+  })
+
+  registerSetting({
+    name: 'prosody-c2s-port',
+    label: 'Prosody client to server port',
+    type: 'input',
+    default: '52822',
+    private: true,
+    descriptionHTML:
+`The port that will be used by the c2s module of the builtin Prosody server.<br>
+XMPP clients shall use this port to connect.<br>
+Change it if this port is already in use on your server.<br>
+Keep it close this port on your firewall for now, it will not be accessed from the outer world.`
+  })
+
   // ********** settings changes management
   settingsManager.onSettingsChange(async (settings: any) => {
     if ('chat-type' in settings) {