diff --git a/CHANGELOG.md b/CHANGELOG.md
index 48e80125..73b4f0cb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Changelog
 
+## ??? (Not Release Yet)
+
+### New Features
+
+* Chat Federation: if both local and remote instance have external XMPP connections enabled, you can use your local xmpp account to join remote rooms.
+
 ## 6.3.0
 
 ### New Features
diff --git a/conversejs/builtin.ts b/conversejs/builtin.ts
index d2e1ce6d..f4e44927 100644
--- a/conversejs/builtin.ts
+++ b/conversejs/builtin.ts
@@ -1,246 +1,77 @@
-// eslint-disable-next-line @typescript-eslint/no-unused-vars
-interface Window {
-  converse: {
-    initialize: (args: any) => void
-    plugins: {
-      add: (name: string, plugin: any) => void
-    }
-  }
-  initConverse: (args: any) => void
-}
+import type { InitConverseParams } from './lib/types'
+import { inIframe } from './lib/utils'
+import { initDom } from './lib/dom'
+import {
+  defaultConverseParams,
+  localRoomAnonymousParams,
+  localRoomAuthenticatedParams,
+  remoteRoomAnonymousParams,
+  remoteRoomAuthenticatedParams
+} from './lib/converse-params'
+import { getLocalAuthentInfos } from './lib/auth'
+import { randomNick } from './lib/nick'
 
-function inIframe (): boolean {
-  try {
-    return window.self !== window.top
-  } catch (e) {
-    return true
+declare global {
+  interface Window {
+    converse: {
+      initialize: (args: any) => void
+      plugins: {
+        add: (name: string, plugin: any) => void
+      }
+    }
+    initConverse: (args: InitConverseParams) => Promise<void>
   }
 }
 
-interface AuthentInfos {
-  jid: string
-  password: string
-  nickname?: string
-}
-async function authenticatedMode (authenticationUrl: string): Promise<false | AuthentInfos> {
-  try {
-    if (!window.fetch) {
-      console.error('Your browser has not the fetch api, we cant log you in')
-      return false
-    }
-    if (!window.localStorage) {
-      // FIXME: is the Peertube token always in localStorage?
-      console.error('Your browser has no localStorage, we cant log you in')
-      return false
-    }
-    const tokenType = window.localStorage.getItem('token_type') ?? ''
-    const accessToken = window.localStorage.getItem('access_token') ?? ''
-    const refreshToken = window.localStorage.getItem('refresh_token') ?? ''
-    if (tokenType === '' && accessToken === '' && refreshToken === '') {
-      console.info('User seems not to be logged in.')
-      return false
-    }
-
-    const response = await window.fetch(authenticationUrl, {
-      method: 'GET',
-      headers: new Headers({
-        Authorization: tokenType + ' ' + accessToken,
-        'content-type': 'application/json;charset=UTF-8'
-      })
-    })
-
-    if (!response.ok) {
-      console.error('Failed fetching user informations')
-      return false
-    }
-    const data = await response.json()
-    if ((typeof data) !== 'object') {
-      console.error('Failed reading user informations')
-      return false
-    }
-
-    if (!data.jid || !data.password) {
-      console.error('User informations does not contain required fields')
-      return false
-    }
-    return {
-      jid: data.jid,
-      password: data.password,
-      nickname: data.nickname
-    }
-  } catch (error) {
-    console.error(error)
-    return false
-  }
-}
-
-function randomNick (base: string): string {
-  // using a 6 digit random number to generate a nickname with low colision risk
-  const n = 100000 + Math.floor(Math.random() * 900000)
-  return base + ' ' + n.toString()
-}
-
-interface InitConverseParams {
-  jid: string
-  remoteAnonymousXMPPServer: boolean
-  assetsPath: string
-  room: string
-  boshServiceUrl: string
-  websocketServiceUrl: string
-  authenticationUrl: string
-  autoViewerMode: boolean
-  forceReadonly: boolean | 'noscroll'
-  noScroll: boolean
-  theme: string
-  transparent: boolean
-}
-window.initConverse = async function initConverse ({
-  jid,
-  remoteAnonymousXMPPServer,
-  assetsPath,
-  room,
-  boshServiceUrl,
-  websocketServiceUrl,
-  authenticationUrl,
-  autoViewerMode,
-  forceReadonly,
-  theme,
-  transparent
-}: InitConverseParams) {
-  const isInIframe = inIframe()
-  const converse = window.converse
-
-  const body = document.querySelector('body')
-  if (isInIframe) {
-    if (body) {
-      body.classList.add('livechat-iframe')
-      // prevent horizontal scrollbar when in iframe. (don't know why, but does not work if done by CSS)
-      body.style.overflowX = 'hidden'
-    }
-  }
-  if (forceReadonly) {
-    body?.classList.add('livechat-readonly')
-    if (forceReadonly === 'noscroll') {
-      body?.classList.add('livechat-noscroll')
-    }
-  }
-  if (transparent) {
-    body?.classList.add('livechat-transparent')
-  }
-
-  if (websocketServiceUrl?.startsWith('/')) {
-    websocketServiceUrl = new URL(
-      websocketServiceUrl,
+window.initConverse = async function initConverse (initConverseParams: InitConverseParams): Promise<void> {
+  // First, fixing relative websocket urls.
+  if (initConverseParams.localWebsocketServiceUrl?.startsWith('/')) {
+    initConverseParams.localWebsocketServiceUrl = new URL(
+      initConverseParams.localWebsocketServiceUrl,
       (window.location.protocol === 'http:' ? 'ws://' : 'wss://') + window.location.host
     ).toString()
   }
 
-  const mucShowInfoMessages = forceReadonly
-    ? [
-        // in readonly mode, show only following info messages:
-        '301', '307', '321', '322', '332', '333' // disconnected
-      ]
-    : [
-        // FIXME: wait for a response here, and rewrite: https://github.com/conversejs/converse.js/issues/3125
-        '100', '102', '103', '172', '173', '174', // visibility_changes
-        '110', // self
-        '104', '201', // non_privacy_changes
-        '170', '171', // muc_logging_changes
-        '210', '303', // nickname_changes
-        '301', '307', '321', '322', '332', '333', // disconnected
-        'owner', 'admin', 'member', 'exadmin', 'exowner', 'exoutcast', 'exmember', // affiliation_changes
-        // 'entered', 'exited', // join_leave_events
-        'op', 'deop', 'voice', 'mute' // role_changes
-      ]
+  const {
+    isRemoteChat,
+    remoteAnonymousXMPPServer,
+    remoteAuthenticatedXMPPServer,
+    authenticationUrl,
+    autoViewerMode,
+    forceReadonly
+  } = initConverseParams
 
-  const params: any = {
-    assets_path: assetsPath,
+  const converse = window.converse
 
-    authentication: 'anonymous',
-    ping_interval: 25, // must be set accordingly to c2s_close_timeout backend websocket settings and nginx timeout
-    auto_login: true,
-    auto_join_rooms: [
-      room
-    ],
-    keepalive: true,
-    discover_connection_methods: false, // this parameter seems buggy with converseJS 7.0.4
-    bosh_service_url: boshServiceUrl === '' ? undefined : boshServiceUrl,
-    websocket_url: websocketServiceUrl === '' ? undefined : websocketServiceUrl,
-    jid: jid,
-    notify_all_room_messages: [
-      room
-    ],
-    show_desktop_notifications: false,
-    show_tab_notifications: false,
-    singleton: true,
-    auto_focus: !isInIframe,
-    hide_muc_participants: isInIframe,
-    play_sounds: false,
-    muc_mention_autocomplete_min_chars: 2,
-    muc_mention_autocomplete_filter: 'contains',
-    muc_instant_rooms: true,
-    show_client_info: false,
-    allow_adhoc_commands: false,
-    allow_contact_requests: false,
-    allow_logout: false,
-    show_controlbox_by_default: false,
-    view_mode: 'fullscreen',
-    allow_message_corrections: 'all',
-    allow_message_retraction: 'all',
-    visible_toolbar_buttons: {
-      call: false,
-      spoiler: false,
-      emoji: true,
-      toggle_occupants: true
-    },
-    theme: theme || 'peertube',
-    dark_theme: theme || 'peertube', // dark theme should be the same as theme
-    persistent_store: 'sessionStorage',
-    show_images_inline: false, // for security reason, and to avoid bugs when image is larger that iframe
-    render_media: false, // for security reason, and to avoid bugs when image is larger that iframe
-    whitelisted_plugins: ['livechatWindowTitlePlugin', 'livechatViewerModePlugin', 'livechatDisconnectOnUnloadPlugin'],
-    show_retraction_warning: false, // No need to use this warning (except if we open to external clients?)
-    muc_show_info_messages: mucShowInfoMessages,
-    send_chat_state_notifications: false // don't send this for performance reason
-  }
-
-  // TODO: params.clear_messages_on_reconnection = true when muc_mam will be available.
+  const isInIframe = inIframe()
+  initDom(initConverseParams, isInIframe)
+  const params = defaultConverseParams(initConverseParams, isInIframe)
 
   let isAuthenticated: boolean = false
   let isRemoteWithNicknameSet: boolean = false
-  if (authenticationUrl === '') {
-    throw new Error('Missing authenticationUrl')
-  }
 
-  // The user will never se the «trusted browser» checkbox (that allows to save credentials).
-  // So we have to disable it
-  // (and ensure clear_cache_on_logout is true,
-  // see https://conversejs.org/docs/html/configuration.html#allow-user-trust-override).
-  params.clear_cache_on_logout = true
-  params.allow_user_trust_override = false
-
-  const auth = await authenticatedMode(authenticationUrl)
+  const auth = await getLocalAuthentInfos(authenticationUrl)
   if (auth) {
-    if (remoteAnonymousXMPPServer) {
-      // Spécial case: anonymous connection to remote XMPP server.
-      if (auth.nickname) {
-        params.nickname = auth.nickname
-        isRemoteWithNicknameSet = true
-      }
-    } else {
-      params.authentication = 'login'
-      params.auto_login = true
-      params.jid = auth.jid
-      params.password = auth.password
-      if (auth.nickname) {
-        params.nickname = auth.nickname
-      } else {
-        params.muc_nickname_from_jid = true
-      }
-      // We dont need the keepalive. And I suppose it is related to some bugs when opening a previous chat window.
-      params.keepalive = false
+    if (!isRemoteChat) {
+      localRoomAuthenticatedParams(initConverseParams, auth, params)
       isAuthenticated = true
-      // FIXME: use params.oauth_providers?
+    } else if (remoteAuthenticatedXMPPServer) {
+      remoteRoomAuthenticatedParams(initConverseParams, auth, params)
+      isAuthenticated = true
+    } else if (remoteAnonymousXMPPServer) {
+      // remote server does not allow remote authenticated users, falling back to anonymous mode
+      remoteRoomAnonymousParams(initConverseParams, auth, params)
+      isRemoteWithNicknameSet = true
+    } else {
+      throw new Error('Remote server does not allow remote connection')
+    }
+  } else {
+    if (!isRemoteChat) {
+      localRoomAnonymousParams(initConverseParams, params)
+    } else if (remoteAnonymousXMPPServer) {
+      remoteRoomAnonymousParams(initConverseParams, null, params)
+    } else {
+      throw new Error('Remote server does not allow remote connection')
     }
   }
 
@@ -300,9 +131,9 @@ window.initConverse = async function initConverse ({
           function refreshViewerMode (canChat: boolean): void {
             console.log('[livechatViewerModePlugin] refreshViewerMode: ' + (canChat ? 'off' : 'on'))
             if (canChat) {
-              body?.setAttribute('livechat-viewer-mode', 'off')
+              document.querySelector('body')?.setAttribute('livechat-viewer-mode', 'off')
             } else {
-              body?.setAttribute('livechat-viewer-mode', 'on')
+              document.querySelector('body')?.setAttribute('livechat-viewer-mode', 'on')
             }
           }
 
diff --git a/conversejs/index.html b/conversejs/index.html
index bdb921a2..1063191f 100644
--- a/conversejs/index.html
+++ b/conversejs/index.html
@@ -15,12 +15,17 @@
 <div id="conversejs-bg" class="theme-peertube"></div>
 <script type="text/javascript">
   initConverse({
-    jid: '{{JID}}',
+    isRemoteChat: '{{IS_REMOTE_CHAT}}' === 'true',
+    localAnonymousJID: '{{LOCAL_ANONYMOUS_JID}}',
+    remoteAnonymousJID: '{{REMOTE_ANONYMOUS_JID}}' === '' ? null : '{{REMOTE_ANONYMOUS_JID}}',
     remoteAnonymousXMPPServer: '{{REMOTE_ANONYMOUS_XMPP_SERVER}}' === 'true',
+    remoteAuthenticatedXMPPServer: '{{REMOTE_AUTHENTICATED_XMPP_SERVER}}' === 'true',
     assetsPath : '{{BASE_STATIC_URL}}conversejs/',
     room: '{{ROOM}}',
-    boshServiceUrl: '{{BOSH_SERVICE_URL}}',
-    websocketServiceUrl: '{{WS_SERVICE_URL}}',
+    localBoshServiceUrl: '{{LOCAL_BOSH_SERVICE_URL}}' === '' ? null : '{{LOCAL_BOSH_SERVICE_URL}}',
+    localWebsocketServiceUrl: '{{LOCAL_WS_SERVICE_URL}}' === '' ? null : '{{LOCAL_WS_SERVICE_URL}}',
+    remoteBoshServiceUrl: '{{REMOTE_BOSH_SERVICE_URL}}' === '' ? null : '{{REMOTE_BOSH_SERVICE_URL}}',
+    remoteWebsocketServiceUrl: '{{REMOTE_WS_SERVICE_URL}}' === '' ? null : '{{REMOTE_WS_SERVICE_URL}}',
     authenticationUrl: '{{AUTHENTICATION_URL}}',
     autoViewerMode: '{{AUTOVIEWERMODE}}' === 'true',
     theme: '{{CONVERSEJS_THEME}}',
diff --git a/conversejs/lib/auth.ts b/conversejs/lib/auth.ts
new file mode 100644
index 00000000..86ff2a3c
--- /dev/null
+++ b/conversejs/lib/auth.ts
@@ -0,0 +1,65 @@
+interface AuthentInfos {
+  jid: string
+  password: string
+  nickname?: string
+}
+async function getLocalAuthentInfos (authenticationUrl: string): Promise<false | AuthentInfos> {
+  try {
+    if (authenticationUrl === '') {
+      console.error('Missing authenticationUrl')
+      return false
+    }
+    if (!window.fetch) {
+      console.error('Your browser has not the fetch api, we cant log you in')
+      return false
+    }
+    if (!window.localStorage) {
+      // FIXME: is the Peertube token always in localStorage?
+      console.error('Your browser has no localStorage, we cant log you in')
+      return false
+    }
+    const tokenType = window.localStorage.getItem('token_type') ?? ''
+    const accessToken = window.localStorage.getItem('access_token') ?? ''
+    const refreshToken = window.localStorage.getItem('refresh_token') ?? ''
+    if (tokenType === '' && accessToken === '' && refreshToken === '') {
+      console.info('User seems not to be logged in.')
+      return false
+    }
+
+    const response = await window.fetch(authenticationUrl, {
+      method: 'GET',
+      headers: new Headers({
+        Authorization: tokenType + ' ' + accessToken,
+        'content-type': 'application/json;charset=UTF-8'
+      })
+    })
+
+    if (!response.ok) {
+      console.error('Failed fetching user informations')
+      return false
+    }
+    const data = await response.json()
+    if ((typeof data) !== 'object') {
+      console.error('Failed reading user informations')
+      return false
+    }
+
+    if (!data.jid || !data.password) {
+      console.error('User informations does not contain required fields')
+      return false
+    }
+    return {
+      jid: data.jid,
+      password: data.password,
+      nickname: data.nickname
+    }
+  } catch (error) {
+    console.error(error)
+    return false
+  }
+}
+
+export {
+  AuthentInfos,
+  getLocalAuthentInfos
+}
diff --git a/conversejs/lib/converse-params.ts b/conversejs/lib/converse-params.ts
new file mode 100644
index 00000000..e650762a
--- /dev/null
+++ b/conversejs/lib/converse-params.ts
@@ -0,0 +1,174 @@
+import type { InitConverseParams } from './types'
+import type { AuthentInfos } from './auth'
+
+/**
+ * Instanciate defaults params to use for ConverseJS.
+ * Note: these parameters must be completed with one of the other function present in this module.
+ * @param param0 global parameters
+ * @param isInIframe true if we are in iframe mode (inside Peertube, beside video)
+ * @returns default parameters to provide to ConverseJS.
+ */
+function defaultConverseParams (
+  { forceReadonly, theme, assetsPath, room }: InitConverseParams,
+  isInIframe: boolean
+): any {
+  const mucShowInfoMessages = forceReadonly
+    ? [
+        // in readonly mode, show only following info messages:
+        '301', '307', '321', '322', '332', '333' // disconnected
+      ]
+    : [
+        // FIXME: wait for a response here, and rewrite: https://github.com/conversejs/converse.js/issues/3125
+        '100', '102', '103', '172', '173', '174', // visibility_changes
+        '110', // self
+        '104', '201', // non_privacy_changes
+        '170', '171', // muc_logging_changes
+        '210', '303', // nickname_changes
+        '301', '307', '321', '322', '332', '333', // disconnected
+        'owner', 'admin', 'member', 'exadmin', 'exowner', 'exoutcast', 'exmember', // affiliation_changes
+        // 'entered', 'exited', // join_leave_events
+        'op', 'deop', 'voice', 'mute' // role_changes
+      ]
+
+  const params: any = {
+    assets_path: assetsPath,
+
+    authentication: 'anonymous',
+    ping_interval: 25, // must be set accordingly to c2s_close_timeout backend websocket settings and nginx timeout
+    auto_login: true,
+    auto_join_rooms: [
+      room
+    ],
+    keepalive: true,
+    discover_connection_methods: false, // this parameter seems buggy with converseJS 7.0.4
+    notify_all_room_messages: [
+      room
+    ],
+    show_desktop_notifications: false,
+    show_tab_notifications: false,
+    singleton: true,
+    auto_focus: !isInIframe,
+    hide_muc_participants: isInIframe,
+    play_sounds: false,
+    muc_mention_autocomplete_min_chars: 2,
+    muc_mention_autocomplete_filter: 'contains',
+    muc_instant_rooms: true,
+    show_client_info: false,
+    allow_adhoc_commands: false,
+    allow_contact_requests: false,
+    allow_logout: false,
+    show_controlbox_by_default: false,
+    view_mode: 'fullscreen',
+    allow_message_corrections: 'all',
+    allow_message_retraction: 'all',
+    visible_toolbar_buttons: {
+      call: false,
+      spoiler: false,
+      emoji: true,
+      toggle_occupants: true
+    },
+    theme: theme || 'peertube',
+    dark_theme: theme || 'peertube', // dark theme should be the same as theme
+    persistent_store: 'sessionStorage',
+    show_images_inline: false, // for security reason, and to avoid bugs when image is larger that iframe
+    render_media: false, // for security reason, and to avoid bugs when image is larger that iframe
+    whitelisted_plugins: ['livechatWindowTitlePlugin', 'livechatViewerModePlugin', 'livechatDisconnectOnUnloadPlugin'],
+    show_retraction_warning: false, // No need to use this warning (except if we open to external clients?)
+    muc_show_info_messages: mucShowInfoMessages,
+    send_chat_state_notifications: false // don't send this for performance reason
+  }
+
+  // TODO: params.clear_messages_on_reconnection = true when muc_mam will be available.
+
+  // The user will never se the «trusted browser» checkbox (that allows to save credentials).
+  // So we have to disable it
+  // (and ensure clear_cache_on_logout is true,
+  // see https://conversejs.org/docs/html/configuration.html#allow-user-trust-override).
+  params.clear_cache_on_logout = true
+  params.allow_user_trust_override = false
+
+  return params
+}
+
+/**
+ * The room is local, and we are an authenticated local user
+ * @param initConverseParams global parameters
+ * @param auth authent infos.
+ * @param params ConverseJS parameters to fill
+ */
+function localRoomAuthenticatedParams (initConverseParams: InitConverseParams, auth: AuthentInfos, params: any): void {
+  _fillAuthenticatedParams(initConverseParams, auth, params)
+  _fillLocalProtocols(initConverseParams, params)
+}
+
+/**
+ * The room is local, and we are an anonymous local user
+ * @param initConverseParams global parameters
+ * @param params ConverseJS parameters to fill
+ */
+function localRoomAnonymousParams (initConverseParams: InitConverseParams, params: any): void {
+  params.jid = initConverseParams.localAnonymousJID
+  _fillLocalProtocols(initConverseParams, params)
+}
+
+/**
+ * The room is remote, and we are an authenticated local user
+ * @param initConverseParams global parameters
+ * @param auth authent infos.
+ * @param params ConverseJS parameters to fill
+ */
+function remoteRoomAuthenticatedParams (initConverseParams: InitConverseParams, auth: AuthentInfos, params: any): void {
+  _fillAuthenticatedParams(initConverseParams, auth, params)
+  _fillLocalProtocols(initConverseParams, params)
+}
+
+/**
+ * The room is remote, and we are an anonymous local user
+ * @param initConverseParams global parameters
+ * @param auth optionnal authent infos. Used to get the default nickname
+ * @param params ConverseJS parameters to fill
+ */
+function remoteRoomAnonymousParams (
+  initConverseParams: InitConverseParams,
+  auth: AuthentInfos | null,
+  params: any
+): void {
+  params.jid = initConverseParams.remoteAnonymousJID
+  if (auth?.nickname) {
+    params.nickname = auth.nickname
+  }
+  _fillRemoteProtocols(initConverseParams, params)
+}
+
+function _fillAuthenticatedParams (initConverseParams: InitConverseParams, auth: AuthentInfos, params: any): void {
+  params.authentication = 'login'
+  params.auto_login = true
+  params.jid = auth.jid
+  params.password = auth.password
+  if (auth.nickname) {
+    params.nickname = auth.nickname
+  } else {
+    params.muc_nickname_from_jid = true
+  }
+  // We dont need the keepalive. And I suppose it is related to some bugs when opening a previous chat window.
+  params.keepalive = false
+  // FIXME: use params.oauth_providers?
+}
+
+function _fillLocalProtocols (initConverseParams: InitConverseParams, params: any): void {
+  params.bosh_service_url = initConverseParams.localBoshServiceUrl
+  params.websocket_url = initConverseParams.localWebsocketServiceUrl
+}
+
+function _fillRemoteProtocols (initConverseParams: InitConverseParams, params: any): void {
+  params.bosh_service_url = initConverseParams.remoteBoshServiceUrl
+  params.websocket_url = initConverseParams.remoteWebsocketServiceUrl
+}
+
+export {
+  defaultConverseParams,
+  localRoomAuthenticatedParams,
+  localRoomAnonymousParams,
+  remoteRoomAnonymousParams,
+  remoteRoomAuthenticatedParams
+}
diff --git a/conversejs/lib/dom.ts b/conversejs/lib/dom.ts
new file mode 100644
index 00000000..6c8705dd
--- /dev/null
+++ b/conversejs/lib/dom.ts
@@ -0,0 +1,25 @@
+import type { InitConverseParams } from './types'
+
+function initDom ({ forceReadonly, transparent }: InitConverseParams, isInIframe: boolean): void {
+  const body = document.querySelector('body')
+  if (isInIframe) {
+    if (body) {
+      body.classList.add('livechat-iframe')
+      // prevent horizontal scrollbar when in iframe. (don't know why, but does not work if done by CSS)
+      body.style.overflowX = 'hidden'
+    }
+  }
+  if (forceReadonly) {
+    body?.classList.add('livechat-readonly')
+    if (forceReadonly === 'noscroll') {
+      body?.classList.add('livechat-noscroll')
+    }
+  }
+  if (transparent) {
+    body?.classList.add('livechat-transparent')
+  }
+}
+
+export {
+  initDom
+}
diff --git a/conversejs/lib/nick.ts b/conversejs/lib/nick.ts
new file mode 100644
index 00000000..1b8d8178
--- /dev/null
+++ b/conversejs/lib/nick.ts
@@ -0,0 +1,9 @@
+function randomNick (base: string): string {
+  // using a 6 digit random number to generate a nickname with low colision risk
+  const n = 100000 + Math.floor(Math.random() * 900000)
+  return base + ' ' + n.toString()
+}
+
+export {
+  randomNick
+}
diff --git a/conversejs/lib/types.ts b/conversejs/lib/types.ts
new file mode 100644
index 00000000..4751e2a1
--- /dev/null
+++ b/conversejs/lib/types.ts
@@ -0,0 +1,23 @@
+interface InitConverseParams {
+  isRemoteChat: boolean
+  localAnonymousJID: string
+  remoteAnonymousJID: string | null
+  remoteAnonymousXMPPServer: boolean
+  remoteAuthenticatedXMPPServer: boolean
+  assetsPath: string
+  room: string
+  localBoshServiceUrl: string | null
+  localWebsocketServiceUrl: string | null
+  remoteBoshServiceUrl: string | null
+  remoteWebsocketServiceUrl: string | null
+  authenticationUrl: string
+  autoViewerMode: boolean
+  forceReadonly: boolean | 'noscroll'
+  noScroll: boolean
+  theme: string
+  transparent: boolean
+}
+
+export {
+  InitConverseParams
+}
diff --git a/conversejs/lib/utils.ts b/conversejs/lib/utils.ts
new file mode 100644
index 00000000..45bb0baf
--- /dev/null
+++ b/conversejs/lib/utils.ts
@@ -0,0 +1,11 @@
+function inIframe (): boolean {
+  try {
+    return window.self !== window.top
+  } catch (e) {
+    return true
+  }
+}
+
+export {
+  inIframe
+}
diff --git a/server/lib/federation/connection-infos.ts b/server/lib/federation/connection-infos.ts
index ca003f7f..1988380a 100644
--- a/server/lib/federation/connection-infos.ts
+++ b/server/lib/federation/connection-infos.ts
@@ -31,6 +31,17 @@ function anonymousConnectionInfos (livechatInfos: LiveChatJSONLDAttribute | fals
   return r
 }
 
-export {
-  anonymousConnectionInfos
+function remoteAuthenticatedConnectionEnabled (livechatInfos: LiveChatJSONLDAttribute | false): boolean {
+  if (!livechatInfos) { return false }
+  if (!livechatInfos.links) { return false }
+  if (livechatInfos.type !== 'xmpp') { return false }
+  for (const link of livechatInfos.links) {
+    if (link.type === 'xmpp-s2s') { return true }
+  }
+  return false
+}
+
+export {
+  anonymousConnectionInfos,
+  remoteAuthenticatedConnectionEnabled
 }
diff --git a/server/lib/federation/outgoing.ts b/server/lib/federation/outgoing.ts
index 2133ed7b..681d9b9e 100644
--- a/server/lib/federation/outgoing.ts
+++ b/server/lib/federation/outgoing.ts
@@ -31,7 +31,8 @@ async function videoBuildJSONLD (
     'disable-websocket',
     'prosody-room-type',
     'federation-dont-publish-remotely',
-    'chat-no-anonymous'
+    'chat-no-anonymous',
+    'prosody-room-allow-s2s'
   ])
 
   if (settings['federation-dont-publish-remotely']) {
@@ -70,6 +71,11 @@ async function videoBuildJSONLD (
   }
 
   const links: LiveChatJSONLDLink[] = []
+  if (settings['prosody-room-allow-s2s']) {
+    links.push({
+      type: 'xmpp-s2s'
+    })
+  }
   if (!settings['chat-no-anonymous']) {
     links.push({
       type: 'xmpp-bosh-anonymous',
diff --git a/server/lib/federation/sanitize.ts b/server/lib/federation/sanitize.ts
index f41a92b1..9e6666ff 100644
--- a/server/lib/federation/sanitize.ts
+++ b/server/lib/federation/sanitize.ts
@@ -36,6 +36,11 @@ function sanitizePeertubeLiveChatInfos (chatInfos: any): LiveChatJSONLDAttribute
         url: link.url
       })
     }
+    if (link.type === 'xmpp-s2s') {
+      r.links.push({
+        type: link.type
+      })
+    }
   }
   return r
 }
diff --git a/server/lib/federation/types.ts b/server/lib/federation/types.ts
index 8f20507b..0dc735b7 100644
--- a/server/lib/federation/types.ts
+++ b/server/lib/federation/types.ts
@@ -4,6 +4,10 @@ interface VideoBuildResultContext {
   video: MVideoAP
 }
 
+interface LiveChatJSONLDS2SLink {
+  type: 'xmpp-s2s'
+}
+
 interface LiveChatJSONLDAnonymousWebsocketLink {
   type: 'xmpp-websocket-anonymous'
   url: string
@@ -16,7 +20,7 @@ interface LiveChatJSONLDAnonymousBOSHLink {
   jid: string
 }
 
-type LiveChatJSONLDLink = LiveChatJSONLDAnonymousBOSHLink | LiveChatJSONLDAnonymousWebsocketLink
+type LiveChatJSONLDLink = LiveChatJSONLDS2SLink | LiveChatJSONLDAnonymousBOSHLink | LiveChatJSONLDAnonymousWebsocketLink
 
 interface LiveChatJSONLDInfos {
   type: 'xmpp'
diff --git a/server/lib/prosody/config.ts b/server/lib/prosody/config.ts
index 8677fb45..66e42fcf 100644
--- a/server/lib/prosody/config.ts
+++ b/server/lib/prosody/config.ts
@@ -156,6 +156,7 @@ async function getProsodyConfig (options: RegisterServerOptionsV5): Promise<Pros
   const prosodyDomain = await getProsodyDomain(options)
   const paths = await getProsodyFilePaths(options)
   const roomType = settings['prosody-room-type'] === 'channel' ? 'channel' : 'video'
+  const enableUserS2S = enableRoomS2S && !(settings['federation-no-remote-chat'] as boolean)
   let certificates: ProsodyConfigCertificates = false
 
   const apikey = await getAPIKey(options)
@@ -203,7 +204,7 @@ async function getProsodyConfig (options: RegisterServerOptionsV5): Promise<Pros
     config.useExternalComponents(componentsPort, components)
   }
 
-  if (enableRoomS2S) {
+  if (enableRoomS2S || enableUserS2S) {
     certificates = 'generate-self-signed'
     if (config.paths.certsDirIsCustom) {
       certificates = 'use-from-dir'
@@ -223,7 +224,7 @@ async function getProsodyConfig (options: RegisterServerOptionsV5): Promise<Pros
       if (networkInterface.match(/^[a-f0-9:]+$/)) return
       throw new Error('Invalid s2s interfaces')
     })
-    config.useRoomS2S(s2sPort, s2sInterfaces)
+    config.useS2S(s2sPort, s2sInterfaces, !enableUserS2S)
   }
 
   const logExpiration = readLogExpiration(options, logExpirationSetting)
diff --git a/server/lib/prosody/config/content.ts b/server/lib/prosody/config/content.ts
index 273b9334..1cf32718 100644
--- a/server/lib/prosody/config/content.ts
+++ b/server/lib/prosody/config/content.ts
@@ -258,13 +258,17 @@ class ProsodyConfigContent {
     this.global.set('c2s_ports', [c2sPort])
   }
 
-  useRoomS2S (s2sPort: string, s2sInterfaces: string[]): void {
+  useS2S (s2sPort: string, s2sInterfaces: string[], mucOnly: boolean): void {
     this.global.set('s2s_ports', [s2sPort])
     this.global.set('s2s_interfaces', s2sInterfaces)
     this.global.set('s2s_secure_auth', false)
     this.global.add('modules_enabled', 'tls') // required for s2s and co
     this.muc.add('modules_enabled', 's2s')
     this.muc.add('modules_enabled', 'dialback') // This allows s2s connections without certicicates!
+    if (!mucOnly && this.authenticated) {
+      this.authenticated.add('modules_enabled', 's2s')
+      this.authenticated.add('modules_enabled', 'dialback') // This allows s2s connections without certicicates!
+    }
   }
 
   useExternalComponents (componentsPort: string, components: ExternalComponent[]): void {
diff --git a/server/lib/routers/webchat.ts b/server/lib/routers/webchat.ts
index a29bdb74..7404d755 100644
--- a/server/lib/routers/webchat.ts
+++ b/server/lib/routers/webchat.ts
@@ -15,7 +15,7 @@ import { isAutoColorsAvailable, areAutoColorsValid, AutoColors } from '../../../
 import { getBoshUri, getWSUri } from '../uri/webchat'
 import { getVideoLiveChatInfos } from '../federation/storage'
 import { LiveChatJSONLDAttribute } from '../federation/types'
-import { anonymousConnectionInfos } from '../federation/connection-infos'
+import { anonymousConnectionInfos, remoteAuthenticatedConnectionEnabled } from '../federation/connection-infos'
 import * as path from 'path'
 const got = require('got')
 
@@ -50,7 +50,8 @@ async function initWebchatRouter (options: RegisterServerOptionsV5): Promise<Rou
         'prosody-room-type',
         'disable-websocket',
         'converse-theme', 'converse-autocolors',
-        'federation-no-remote-chat'
+        'federation-no-remote-chat',
+        'prosody-room-allow-s2s'
       ])
 
       let autoViewerMode: boolean = false
@@ -110,26 +111,38 @@ async function initWebchatRouter (options: RegisterServerOptionsV5): Promise<Rou
       const baseStaticUrl = getBaseStaticRoute(options)
       page = page.replace(/{{BASE_STATIC_URL}}/g, baseStaticUrl)
 
-      let connectionInfos: ConnectionInfos | null
+      const prosodyDomain = await getProsodyDomain(options)
+      const localAnonymousJID = 'anon.' + prosodyDomain
+      const localBoshUri = getBoshUri(options)
+      const localWsUri = settings['disable-websocket']
+        ? ''
+        : (getWSUri(options) ?? '')
+
+      let remoteConnectionInfos: WCRemoteConnectionInfos | undefined
+      let roomJID: string
       if (video?.remote) {
-        connectionInfos = await _remoteConnectionInfos(remoteChatInfos ?? false)
+        remoteConnectionInfos = await _remoteConnectionInfos(remoteChatInfos ?? false)
+        if (!remoteConnectionInfos) {
+          res.status(404)
+          res.send('No compatible way to connect to remote chat')
+          return
+        }
+        roomJID = remoteConnectionInfos.roomJID
       } else {
-        connectionInfos = await _localConnectionInfos(
+        roomJID = await _localRoomJID(
           options,
           settings,
+          prosodyDomain,
           roomKey,
           video,
           channelId,
           req.query.forcetype === '1'
         )
       }
-      if (!connectionInfos) {
-        res.status(404)
-        res.send('No compatible way to connect to remote chat')
-        return
-      }
 
-      page = page.replace(/{{JID}}/g, connectionInfos.userJID)
+      page = page.replace(/{{IS_REMOTE_CHAT}}/g, video?.remote ? 'true' : 'false')
+      page = page.replace(/{{LOCAL_ANONYMOUS_JID}}/g, localAnonymousJID)
+      page = page.replace(/{{REMOTE_ANONYMOUS_JID}}/g, remoteConnectionInfos?.anonymous?.userJID ?? '')
 
       let autocolorsStyles = ''
       if (
@@ -183,10 +196,20 @@ async function initWebchatRouter (options: RegisterServerOptionsV5): Promise<Rou
       }
 
       // ... then inject it in the page.
-      page = page.replace(/{{ROOM}}/g, connectionInfos.roomJID)
-      page = page.replace(/{{BOSH_SERVICE_URL}}/g, connectionInfos.boshUri)
-      page = page.replace(/{{WS_SERVICE_URL}}/g, connectionInfos.wsUri ?? '')
-      page = page.replace(/{{REMOTE_ANONYMOUS_XMPP_SERVER}}/g, connectionInfos.remoteXMPPServer ? 'true' : 'false')
+      page = page.replace(/{{ROOM}}/g, roomJID)
+      page = page.replace(/{{LOCAL_BOSH_SERVICE_URL}}/g, localBoshUri)
+      page = page.replace(/{{LOCAL_WS_SERVICE_URL}}/g, localWsUri ?? '')
+      page = page.replace(/{{REMOTE_BOSH_SERVICE_URL}}/g, remoteConnectionInfos?.anonymous?.boshUri ?? '')
+      page = page.replace(/{{REMOTE_WS_SERVICE_URL}}/g, remoteConnectionInfos?.anonymous?.wsUri ?? '')
+      page = page.replace(/{{REMOTE_ANONYMOUS_XMPP_SERVER}}/g, remoteConnectionInfos?.anonymous ? 'true' : 'false')
+      // Note: to be able to connect to remote XMPP server, with a local account,
+      // we must enable prosody-room-allow-s2s
+      // (which is required, so we can use outgoing S2S from the authenticated virtualhost).
+      // TODO: There should be another settings, rather than prosody-room-allow-s2s
+      page = page.replace(
+        /{{REMOTE_AUTHENTICATED_XMPP_SERVER}}/g,
+        settings['prosody-room-allow-s2s'] && remoteConnectionInfos?.authenticated ? 'true' : 'false'
+      )
       page = page.replace(/{{AUTHENTICATION_URL}}/g, authenticationUrl)
       page = page.replace(/{{AUTOVIEWERMODE}}/g, autoViewerMode ? 'true' : 'false')
       page = page.replace(/{{CONVERSEJS_THEME}}/g, converseJSTheme)
@@ -382,44 +405,45 @@ async function enableProxyRoute (
   })
 }
 
-interface ConnectionInfos {
-  userJID: string
+interface WCRemoteConnectionInfos {
   roomJID: string
-  boshUri: string
-  wsUri?: string
-  remoteXMPPServer: boolean
+  anonymous?: {
+    userJID: string
+    boshUri: string
+    wsUri?: string
+  }
+  authenticated?: boolean
 }
 
-async function _remoteConnectionInfos (remoteChatInfos: LiveChatJSONLDAttribute): Promise<ConnectionInfos | null> {
+async function _remoteConnectionInfos (remoteChatInfos: LiveChatJSONLDAttribute): Promise<WCRemoteConnectionInfos> {
   if (!remoteChatInfos) { throw new Error('Should have remote chat infos for remote videos') }
-  const connectionInfos = anonymousConnectionInfos(remoteChatInfos ?? false)
-  if (!connectionInfos || !connectionInfos.boshUri) {
-    return null
+  if (remoteChatInfos.type !== 'xmpp') { throw new Error('Should have remote xmpp chat infos for remote videos') }
+  const connectionInfos: WCRemoteConnectionInfos = {
+    roomJID: remoteChatInfos.jid
   }
-  return {
-    userJID: connectionInfos.userJID,
-    roomJID: connectionInfos.roomJID,
-    boshUri: connectionInfos.boshUri,
-    wsUri: connectionInfos.wsUri,
-    remoteXMPPServer: true
+  if (remoteAuthenticatedConnectionEnabled(remoteChatInfos)) {
+    connectionInfos.authenticated = true
   }
+  const anonymousCI = anonymousConnectionInfos(remoteChatInfos ?? false)
+  if (anonymousCI?.boshUri) {
+    connectionInfos.anonymous = {
+      userJID: anonymousCI.userJID,
+      boshUri: anonymousCI.boshUri,
+      wsUri: anonymousCI.wsUri
+    }
+  }
+  return connectionInfos
 }
 
-async function _localConnectionInfos (
+async function _localRoomJID (
   options: RegisterServerOptions,
   settings: SettingEntries,
+  prosodyDomain: string,
   roomKey: string,
   video: MVideoThumbnail | undefined,
   channelId: number,
   forceType: boolean
-): Promise<ConnectionInfos> {
-  const prosodyDomain = await getProsodyDomain(options)
-  const jid = 'anon.' + prosodyDomain
-  const boshUri = getBoshUri(options)
-  const wsUri = settings['disable-websocket']
-    ? ''
-    : (getWSUri(options) ?? '')
-
+): Promise<string> {
   // Computing the room name...
   let room: string
   if (forceType) {
@@ -462,13 +486,7 @@ async function _localConnectionInfos (
     room = room.replace(/{{CHANNEL_NAME}}/g, channelName)
   }
 
-  return {
-    userJID: jid,
-    roomJID: room,
-    boshUri,
-    wsUri,
-    remoteXMPPServer: false
-  }
+  return room
 }
 
 export {