Index: openacs-4/packages/chat/www/resources/chat.css
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/chat/www/resources/Attic/chat.css,v
diff -u -r1.8 -r1.9
--- openacs-4/packages/chat/www/resources/chat.css	9 Nov 2018 16:48:36 -0000	1.8
+++ openacs-4/packages/chat/www/resources/chat.css	12 Nov 2018 16:35:32 -0000	1.9
@@ -6,6 +6,7 @@
 #xowiki-chat-container {
     height: 70vh;
     width: 100%;
+    position: relative;
 }
 
 /* Users and messages container */
@@ -18,6 +19,21 @@
     background-color: white;
 }
 
+#xowiki-chat-fs {
+    height: 100vh;
+    width: 100%;
+    overflow: hidden;
+    display: flex;
+    background-color: white;
+
+    position: fixed;
+    top: 0;
+    right: 0;
+    bottom: 0;
+    left: 0;
+    zIndex: 999;
+}
+
 /* Users block */
 #xowiki-chat-users {
     border: 1px solid #ddd;
@@ -129,11 +145,32 @@
     border-radius: 8px;
 }
 
+/* Full screen trigger */
+.xowiki-chat-trigger-fs-block {
+    padding: 10px;
+}
+
+.xowiki-chat-trigger-fs-link {
+    text-decoration: none;
+}
+
+.xowiki-chat-trigger-fs-link:hover {
+    text-decoration: none !important;
+}
+
+.xowiki-chat-trigger-fs-pic:hover {
+    background-color: white;
+    border: 1px solid white;
+}
+
 /* Responsive design */
 @media (max-width: 1000px) {
     #xowiki-chat {
         flex-direction: column;
     }
+    #xowiki-chat-fs {
+        flex-direction: column;
+    }
     #xowiki-chat-users {
         order: 1;
         border-left: 1px solid #ddd;
Index: openacs-4/packages/xowiki/tcl/chat-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/chat-procs.tcl,v
diff -u -r1.37 -r1.38
--- openacs-4/packages/xowiki/tcl/chat-procs.tcl	9 Nov 2018 20:09:40 -0000	1.37
+++ openacs-4/packages/xowiki/tcl/chat-procs.tcl	12 Nov 2018 16:35:32 -0000	1.38
@@ -113,6 +113,9 @@
                         -package_key "chat" \
                         -parameter "LinkRegex"]
 
+    # Should we add a full screen link to the chat?
+    set fs_link_p true
+
     # small JavaScript library to obtain a portable ajax request object
     template::head::add_javascript -src urn:ad:js:get-http-object -order 10
     template::head::add_javascript -script "const linkRegex = \"${link_regex}\";" -order 19
@@ -163,15 +166,23 @@
     set data [c1 login]
     if {$data ne ""} {
       append html [subst {
-      <script nonce='$::__csp_nonce'>
-         var data = $data;
-         for(var i = 0; i < data.length; i++) {
+        <script nonce='$::__csp_nonce'>
+          var data = $data;
+          for(var i = 0; i < data.length; i++) {
             renderData(data\[i\]);
-         }
+          }
         </script>
       }]
     }
 
+    if {$fs_link_p} {
+      append html [subst {
+        <script nonce='$::__csp_nonce'>
+          addFullScreenLink();
+        </script>
+      }]
+    }
+
     switch -- $mode {
       "polling" {
         append html [subst -nocommands {
Index: openacs-4/packages/xowiki/www/ajax/chat-common.js
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/www/ajax/Attic/chat-common.js,v
diff -u -r1.5 -r1.6
--- openacs-4/packages/xowiki/www/ajax/chat-common.js	9 Nov 2018 20:09:40 -0000	1.5
+++ openacs-4/packages/xowiki/www/ajax/chat-common.js	12 Nov 2018 16:35:32 -0000	1.6
@@ -3,6 +3,43 @@
 var previous_user_id = "";
 var current_color = "";
 
+// Full screen
+function addFullScreenLink() {
+
+    // Full screen trigger block
+    const triggerFSblock = document.createElement("div");
+    triggerFSblock.className = 'xowiki-chat-trigger-fs-block';
+
+    // Full screen trigger
+    const triggerFSlink = document.createElement("a");
+    triggerFSlink.className = 'xowiki-chat-trigger-fs-link';
+    triggerFSlink.setAttribute("href", "javascript:void(0)");
+
+    // Trigger icon
+    var triggerFSoff = '<svg class="xowiki-chat-trigger-fs-pic" xmlns="http://www.w3.org/2000/svg" width="30" height="30" viewBox="0 0 12 14" preserveAspectRatio="xMidYMin meet"><g stroke-width=".033882" fill="#b3b3b3"><path d="m4.994 10.008v2.1596l-0.6017-0.602-0.6017-0.601-1.0668 1.068c-0.58675 0.58697-1.0823 1.0672-1.1012 1.0672-0.04453 0-1.5755-1.5315-1.5755-1.576 0-0.0186 0.49551-0.52914 1.1011-1.1345l1.1011-1.1007-0.71966-0.72024-0.71966-0.72024h4.1838z"/><path d="m9.7119 8.5856-0.71966 0.72024 1.0842 1.0838c0.5963 0.59609 1.0842 1.0993 1.0842 1.1182 0 0.01889-0.3507 0.38481-0.77933 0.81314l-0.7791 0.779-1.0758-1.076-1.0759-1.075-0.6182 0.618-0.6182 0.618v-4.3196h2.1089 2.1089z"/><path d="m2.8589 2.4267 1.0838 1.0842 0.60168-0.60099 0.60168-0.60099v2.1258 2.1258h-4.0148l0.6182-0.6182 0.6182-0.6182-1.1602-1.1606-1.1602-1.1606 0.82964-0.83016c0.4563-0.45658 0.84509-0.83016 0.86398-0.83016 0.01888 0 0.52204 0.48787 1.1181 1.0842z"/><path d="m10.331 2.1727 0.82964 0.83016-1.1602 1.1606-1.1602 1.1606 0.6182 0.6182 0.6182 0.6182h-3.9814v-4.3194l0.61862 0.61794 0.61862 0.61794 1.0668-1.0672c0.58675-0.58697 1.0747-1.0672 1.0842-1.0672 0.0096 0 0.39074 0.37357 0.84704 0.83016z"/></g></svg>';
+    var triggerFSon = '<svg class="xowiki-chat-trigger-fs-pic" xmlns="http://www.w3.org/2000/svg" width="30" height="30" viewBox="0 0 12 14" preserveAspectRatio="xMidYMin meet"><path stroke-width=".033882" fill="#b3b3b3" d="m0.047182 10.94v-2.1595l0.60168 0.60099 0.60168 0.60099 1.0668-1.0672c0.58675-0.58697 1.0823-1.0672 1.1012-1.0672 0.04453 0 1.5755 1.5315 1.5755 1.576 0 0.0186-0.49551 0.52914-1.1011 1.1345l-1.1011 1.1007 0.71966 0.72024 0.71966 0.72024h-4.1838zm7.6153 1.4394 0.71966-0.72024-1.0842-1.0838c-0.5963-0.5956-1.0842-1.0988-1.0842-1.1177 0-0.01889 0.3507-0.38481 0.77933-0.81314l0.77933-0.77878 1.0759 1.0755 1.0759 1.0755 0.6182-0.6182 0.6182-0.6182v4.3198h-4.2182zm-5.3282-6.9032-1.0838-1.0842-0.60168 0.60099-0.60168 0.60099v-4.2516h4.0148l-0.6182 0.6182-0.6182 0.6182 1.1602 1.1606 1.1602 1.1606-0.82964 0.83016c-0.4563 0.45658-0.84509 0.83016-0.86398 0.83016-0.01888 0-0.52204-0.48787-1.1181-1.0842zm4.591 0.25401-0.82964-0.83016 1.1602-1.1606 1.1602-1.1606-0.6182-0.6182-0.6182-0.6182h3.981v4.3194l-0.61862-0.61794-0.61862-0.61794-1.0668 1.0672c-0.58675 0.58697-1.0747 1.0672-1.0842 1.0672-0.0096 0-0.39074-0.37357-0.84704-0.83016z"/></svg>';
+    triggerFSlink.innerHTML = triggerFSon;
+
+    // Full screen when clicked
+    triggerFSlink.onclick = () => {
+        var chat = document.getElementById('xowiki-chat');
+        var chatFS = document.getElementById('xowiki-chat-fs');
+        if (chat != null) {
+            chat.id = 'xowiki-chat-fs';
+            triggerFSlink.innerHTML = triggerFSoff;
+        } else if (chatFS != null) {
+            chatFS.id = 'xowiki-chat';
+            triggerFSlink.innerHTML = triggerFSon;
+        }
+    }
+
+    // Add Full screen trigger to the chat
+    const formBlock = document.getElementById('xowiki-chat-messages-form-block');
+    triggerFSblock.appendChild(triggerFSlink);
+    formBlock.appendChild(triggerFSblock);
+}
+
+// Simple function to create links
 function createLink(text) {
     if (linkRegex != null) {
         return text.replace(new RegExp(linkRegex,'g'), function(url) {
@@ -13,6 +50,7 @@
     }
 }
 
+// Render the data, being a user or a message
 function renderData(json) {
     if (json.type == "message") {
         renderMessage(json);
@@ -21,6 +59,7 @@
     }
 }
 
+// Render the message
 function renderMessage(msg) {
     var messages = document.getElementById('xowiki-chat-messages');
     var user = msg.user.replace(/\\'/g, "\"");
@@ -91,6 +130,7 @@
     document.getElementById('xowiki-chat-send').focus();
 }
 
+// Render the user in the user list
 function renderUsers(msg) {
     var users = document.getElementById('xowiki-chat-users');
     while (users.hasChildNodes()) {
@@ -129,6 +169,7 @@
     }
 }
 
+// Send the message
 function chatSendMsg(send_url, handler) {
     var msgField = document.getElementById('xowiki-chat-send');
     var msg = msgField.value;