1 files changed, 7 insertions, 19 deletions

diff --git a/netwerk/protocol/http/UserAgentOverrides.jsm b/netwerk/protocol/http/UserAgentOverrides.jsm
index 425bdfd72..aa1325a64 100644
--- a/netwerk/protocol/http/UserAgentOverrides.jsm
+++ b/netwerk/protocol/http/UserAgentOverrides.jsm
@@ -30,7 +30,6 @@ XPCOMUtils.defineLazyServiceGetter(this, "ppmm",
 var gPrefBranch;
 var gOverrides = new Map;
 var gUpdatedOverrides;
-var gOldDynOverrides;
 var gOverrideForHostCache = new Map;
 var gInitialized = false;
 var gOverrideFunctions = [
@@ -56,10 +55,7 @@ this.UserAgentOverrides = {
     }
 
     UserAgentUpdates.init(function(overrides) {
-      if (overrides == gOldDynOverrides) {
-        return;
-      }
-      gOldDynOverrides = overrides;
+      gOverrideForHostCache.clear();
       if (overrides) {
         for (let domain in overrides) {
           overrides[domain] = getUserAgentFromOverride(overrides[domain]);
@@ -67,7 +63,6 @@ this.UserAgentOverrides = {
         overrides.get = function(key) { return this[key]; };
       }
       gUpdatedOverrides = overrides;
-      buildOverrides();
     });
 
     buildOverrides();
@@ -164,22 +159,15 @@ function buildOverrides() {
   if (!Services.prefs.getBoolPref(PREF_OVERRIDES_ENABLED))
     return;
 
+  let builtUAs = new Map;
   let domains = gPrefBranch.getChildList("");
 
-  // Since the static override map has the highest priority, we build it so
-  // that it includes only domains with user-set overrides and domains with
-  // default pre-set overrides that are not overridden by dynamic updates.
   for (let domain of domains) {
-    if (!(gUpdatedOverrides && gUpdatedOverrides.get(domain)) ||
-        gPrefBranch.prefHasUserValue(domain)) {
-      // Here we selected domains that are not dynamically overridden
-      // or have a user-set override.
-      let override = gPrefBranch.getCharPref(domain);
-      let userAgent = getUserAgentFromOverride(override);
-
-      if (userAgent != DEFAULT_UA) {
-        gOverrides.set(domain, userAgent);
-      }
+    let override = gPrefBranch.getCharPref(domain);
+    let userAgent = getUserAgentFromOverride(override);
+
+    if (userAgent != DEFAULT_UA) {
+      gOverrides.set(domain, userAgent);
     }
   }
 }