tor-browser

commit 3c3f7ac9ec21d9c0a0c941ae709f000bacefae3e
parent 77c4df94e78bf73c33b75c9afea2def173e2b675
Author: Tom Ritter <tom@mozilla.com>
Date:   Mon, 29 Dec 2025 20:28:58 +0000

Bug 2005864: Add a metric reporting the web-exposed timezone offset r=timhuang

Differential Revision: https://phabricator.services.mozilla.com/D276712

Diffstat:
M
toolkit/components/resistfingerprinting/UserCharacteristicsPageService.sys.mjs
 | 
1
+
M
toolkit/components/resistfingerprinting/content/usercharacteristics.js
 | 
3
+++
M
toolkit/components/resistfingerprinting/metrics.yaml
 | 
19
+++++++++++++++++++
M
toolkit/components/resistfingerprinting/nsUserCharacteristics.cpp
 | 
2
+-

4 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/toolkit/components/resistfingerprinting/UserCharacteristicsPageService.sys.mjs b/toolkit/components/resistfingerprinting/UserCharacteristicsPageService.sys.mjs
@@ -666,6 +666,7 @@ export class UserCharacteristicsPageService {
         "audioRate",
         "audioChannels",
         "timezoneWeb",
+        "timezoneOffsetWeb",
       ],
     };
 
diff --git a/toolkit/components/resistfingerprinting/content/usercharacteristics.js b/toolkit/components/resistfingerprinting/content/usercharacteristics.js
@@ -999,12 +999,15 @@ async function populateAudioDeviceProperties() {
 async function populateTimezoneWeb() {
   try {
     const timezone = Intl.DateTimeFormat().resolvedOptions().timeZone;
+    const offset = new Date().getTimezoneOffset();
     return {
       timezoneWeb: timezone || "",
+      timezoneOffsetWeb: offset,
     };
   } catch (e) {
     return {
       timezoneWeb: "",
+      timezoneOffsetWeb: 0,
     };
   }
 }
diff --git a/toolkit/components/resistfingerprinting/metrics.yaml b/toolkit/components/resistfingerprinting/metrics.yaml
@@ -421,6 +421,25 @@ characteristics:
     data_sensitivity:
       - interaction
 
+  timezone_offset_web:
+    type: quantity
+    unit: minutes
+    description: >
+      The timezone offset in minutes exposed to web content via getTimezoneOffset()
+    lifetime: application
+    send_in_pings:
+      - user-characteristics
+    notification_emails:
+      - tom@mozilla.com
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1879151
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=2005864
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=2005864
+    expires: never
+    data_sensitivity:
+      - interaction
+
   system_locale:
     type: string
     description: >
diff --git a/toolkit/components/resistfingerprinting/nsUserCharacteristics.cpp b/toolkit/components/resistfingerprinting/nsUserCharacteristics.cpp
@@ -801,7 +801,7 @@ const RefPtr<PopulatePromise>& TimoutPromise(
 // metric is set, this variable should be incremented. It'll be a lot. It's
 // okay. We're going to need it to know (including during development) what is
 // the source of the data we are looking at.
-const int kSubmissionSchema = 28;
+const int kSubmissionSchema = 29;
 
 const auto* const kUUIDPref =
     "toolkit.telemetry.user_characteristics_ping.uuid";