Bug 1918009 - Fix the RFP-spoofed User-Agent header. r=tjr

The spoofed value of the HTTP user-agent header is not consistent with
the value of navigator.userAgent on Windows, and this can lead to
compatibility issues.

Differential Revision: https://phabricator.services.mozilla.com/D223745

browser/components/resistfingerprinting/test/browser/browser_navigator.js

@@ -115,11 +115,11 @@ const SPOOFED_UA_NAVIGATOR_OS = {
   other: "X11; Linux x86_64",
 };
 const SPOOFED_UA_HTTPHEADER_OS = {
-  linux: "Windows NT 10.0",
-  win: "Windows NT 10.0",
-  macosx: "Windows NT 10.0",
+  linux: "Windows NT 10.0; Win64; x64",
+  win: "Windows NT 10.0; Win64; x64",
+  macosx: "Windows NT 10.0; Win64; x64",
   android: "Android 10; Mobile",
-  other: "Windows NT 10.0",
+  other: "Windows NT 10.0; Win64; x64",
 };
 const SPOOFED_HW_CONCURRENCY = 2;
 

browser/components/resistfingerprinting/test/browser/browser_navigator_iframes.js

@@ -130,11 +130,11 @@ const SPOOFED_UA_NAVIGATOR_OS = {
   other: "X11; Linux x86_64",
 };
 const SPOOFED_UA_HTTPHEADER_OS = {
-  linux: "Windows NT 10.0",
-  win: "Windows NT 10.0",
-  macosx: "Windows NT 10.0",
+  linux: "Windows NT 10.0; Win64; x64",
+  win: "Windows NT 10.0; Win64; x64",
+  macosx: "Windows NT 10.0; Win64; x64",
   android: "Android 10; Mobile",
-  other: "Windows NT 10.0",
+  other: "Windows NT 10.0; Win64; x64",
 };
 const SPOOFED_HW_CONCURRENCY = 2;
 

toolkit/components/resistfingerprinting/nsRFPService.h

@@ -64,7 +64,7 @@
 #if defined(MOZ_WIDGET_ANDROID)
 #  define SPOOFED_HTTP_UA_OS "Android 10; Mobile"
 #else
-#  define SPOOFED_HTTP_UA_OS "Windows NT 10.0"
+#  define SPOOFED_HTTP_UA_OS "Windows NT 10.0; Win64; x64"
 #endif
 
 struct JSContext;