diff --git a/src/mibew/libs/chat.php b/src/mibew/libs/chat.php
index 2e50dbcd..d14fb5f8 100644
--- a/src/mibew/libs/chat.php
+++ b/src/mibew/libs/chat.php
@@ -90,107 +90,6 @@ function get_user_name($user_name, $addr, $id)
     );
 }
 
-/**
- * Check if browser support ajax requests
- *
- * @param array $browser_id name of browser
- * @param array $ver browser version
- * @param array $user_agent user agent of browser
- *
- * @return bool true on ajax support and false if ajax is not supported
- */
-function is_ajax_browser($browser_id, $ver, $user_agent)
-{
-    if ($browser_id == "opera") {
-        return $ver >= 8.02;
-    }
-    if ($browser_id == "safari") {
-        return $ver >= 125;
-    }
-    if ($browser_id == "msie") {
-        return $ver >= 5.5 && !strstr($user_agent, "powerpc");
-    }
-    if ($browser_id == "netscape") {
-        return $ver >= 7.1;
-    }
-    if ($browser_id == "mozilla") {
-        return $ver >= 1.4;
-    }
-    if ($browser_id == "firefox") {
-        return $ver >= 1.0;
-    }
-    if ($browser_id == "chrome") {
-        return true;
-    }
-
-    return false;
-}
-
-/**
- * Check if browser support ajax requests
- *
- * @param array $browser_id Code name of browser
- * @param array $ver Browser version
- * @param array $user_agent User Agent of browser
- *
- * @return bool true on ajax support and false if ajax is not supported
- */
-function get_remote_level($user_agent)
-{
-    $known_agents = get_known_user_agents();
-    $user_agent = strtolower($user_agent);
-    foreach ($known_agents as $agent) {
-        if (strstr($user_agent, $agent)) {
-            if (preg_match("/" . $agent . "[\\s\/]?(\\d+(\\.\\d+)?)/", $user_agent, $matches)) {
-                $ver = $matches[1];
-
-                if (is_ajax_browser($agent, $ver, $user_agent)) {
-                    return "ajaxed";
-                } else {
-                    return "old";
-                }
-            }
-        }
-    }
-
-    return "ajaxed";
-}
-
-/**
- * Returns a list of supported browsers.
- *
- * @return array List of supported browsers names.
- */
-function get_supported_browsers()
-{
-    return array(
-        'Internet Explorer 5.5+',
-        'Firefox 1.0+',
-        'Opera 8.0+',
-        'Mozilla 1.4+',
-        'Netscape 7.1+',
-        'Safari 1.2+',
-    );
-}
-
-/**
- * Returns a list of known user agents code names.
- *
- * @return array List of known user agents
- */
-function get_known_user_agents()
-{
-    return array(
-        "opera",
-        "msie",
-        "chrome",
-        "safari",
-        "firefox",
-        "netscape",
-        "mozilla",
-    );
-}
-
 /**
  * Prepare logo data
  *
diff --git a/src/mibew/libs/classes/Mibew/Controller/Chat/OperatorChatController.php b/src/mibew/libs/classes/Mibew/Controller/Chat/OperatorChatController.php
index f836484d..436ed376 100644
--- a/src/mibew/libs/classes/Mibew/Controller/Chat/OperatorChatController.php
+++ b/src/mibew/libs/classes/Mibew/Controller/Chat/OperatorChatController.php
@@ -95,12 +95,6 @@ class OperatorChatController extends AbstractController
         $operator = $this->getOperator();
         $thread_id = $request->attributes->getInt('thread_id');
 
-        // Check operator's browser level because old browsers aren't supported.
-        $remote_level = get_remote_level($request->headers->get('User-Agent'));
-        if ($remote_level != 'ajaxed') {
-            return $this->showErrors(array(getlocal('Old browser is used, please update it')));
-        }
-
         // Check if the thread can be loaded.
         $thread = Thread::load($thread_id);
         if (!$thread || !isset($thread->lastToken)) {
diff --git a/src/mibew/libs/classes/Mibew/Controller/Chat/UserChatController.php b/src/mibew/libs/classes/Mibew/Controller/Chat/UserChatController.php
index 068f5877..78528e9f 100644
--- a/src/mibew/libs/classes/Mibew/Controller/Chat/UserChatController.php
+++ b/src/mibew/libs/classes/Mibew/Controller/Chat/UserChatController.php
@@ -89,15 +89,6 @@ class UserChatController extends AbstractController
             return $ssl_redirect;
         }
 
-        // Do not support old browsers at all
-        if (get_remote_level($request->headers->get('User-Agent')) == 'old') {
-            // Create page array
-            $page = setup_logo();
-            $page['supportedBrowsers'] = get_supported_browsers();
-
-            return $this->render('nochat', $page);
-        }
-
         // Initialize client side application
         $this->getAssetManager()->attachJs('js/compiled/chat_app.js');
 
diff --git a/src/mibew/styles/chats/default/templates_src/server_side/nochat.handlebars b/src/mibew/styles/chats/default/templates_src/server_side/nochat.handlebars
deleted file mode 100644
index ad8e4957..00000000
--- a/src/mibew/styles/chats/default/templates_src/server_side/nochat.handlebars
+++ /dev/null
@@ -1,19 +0,0 @@
-{{#extends "_layout"}}
-    {{#override "pageTitle"}}{{l10n "Error"}}{{/override}}
-
-    {{#override "buttons"}}
-        <a href="javascript:window.close();" title="{{l10n 'Close...'}}">
-            <img class="tpl-image image-close-window" src="{{asset "@CurrentStyle/images/free.gif"}}" alt="{{l10n 'Close...'}}" />
-        </a>
-    {{/override}}
-
-    {{#override "message"}}<p>{{l10n "Your web browser is not fully supported. \nPlease, use one of the following web browsers:"}}</p>{{/override}}
-
-    {{#override "content"}}
-        <ul>
-            {{#each supportedBrowsers}}
-            <li>{{this}}</li>
-            {{/each}}
-        </ul>
-    {{/override}}
-{{/extends}}
\ No newline at end of file