Drop dependency on JsTimeZoneDetect (#8965)

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Unreleased
 
 - Update to jQuery 3.6.3
+- Drop dependency on JsTimeZoneDetect (#8965)
 - Removed support for MS SQL Server and Oracle (#7854)
 - Store uploads metadata in a separate sql database table instead of a session (#8415)
 - Advanced mail search syntax with more possibilities (without UI) (#8502)

jsdeps.json

@@ -11,17 +11,6 @@
       "copyright": "Copyright JS Foundation and other contributors",
       "source": "https://github.com/jquery/jquery/tree/$v"
     },
-    {
-      "lib": "jstz",
-      "name": "jsTimezoneDetect",
-      "version": "1.0.7",
-      "url": "https://cdnjs.cloudflare.com/ajax/libs/jstimezonedetect/1.0.7/jstz.min.js",
-      "dest": "program/js/jstz.min.js",
-      "sha1": "a858ff12014b232fcc7c4c2e9f014ff852ddb917",
-      "license": "MIT",
-      "copyright": "Copyright (c) Jon Nylander",
-      "source": "https://cdnjs.cloudflare.com/ajax/libs/jstimezonedetect/1.0.7/jstz.min.js"
-    },
     {
       "lib": "publickey",
       "name": "PublicKey.js",

program/include/rcmail_output_html.php

@@ -2468,9 +2468,6 @@ EOF;
             $out = $this->form_tag(['name' => $form_name, 'method' => 'post'], $out);
         }
 
-        // include script for timezone detection
-        $this->include_script('jstz.min.js');
-
         return $out;
     }
 

program/js/app.js

@@ -589,8 +589,7 @@ function rcube_webmail()
         break;
 
       case 'login':
-        var tz, tz_name,
-            input_user = $('#rcmloginuser'),
+        var tz, input_user = $('#rcmloginuser');
             input_tz = $('#rcmlogintz');
 
         if (input_user.val() == '')
@@ -599,10 +598,11 @@ function rcube_webmail()
           $('#rcmloginpwd').focus();
 
         // detect client timezone
-        if (window.jstz && (tz = jstz.determine()))
-          tz_name = tz.name();
+        try {
+            tz = Intl.DateTimeFormat().resolvedOptions().timeZone
+        } catch (e) { };
 
-        input_tz.val(tz_name ? tz_name : (new Date().getStdTimezoneOffset() / -60));
+        input_tz.val(tz ? tz : (new Date().getStdTimezoneOffset() / -60));
 
         // display 'loading' message on form submit, lock submit button
         $('form').submit(function () {