1 files changed, 14 insertions, 0 deletions
diff --git a/toolkit/components/antitracking/bouncetrackingprotection/BounceTrackingStateGlobal.cpp b/toolkit/components/antitracking/bouncetrackingprotection/BounceTrackingStateGlobal.cpp
index b94c887c90..bcd9e57bd8 100644
--- a/toolkit/components/antitracking/bouncetrackingprotection/BounceTrackingStateGlobal.cpp
+++ b/toolkit/components/antitracking/bouncetrackingprotection/BounceTrackingStateGlobal.cpp
@@ -9,6 +9,7 @@
 #include "ErrorList.h"
 #include "mozilla/Assertions.h"
 #include "mozilla/Logging.h"
+#include "mozilla/IntegerPrintfMacros.h"
 #include "nsIPrincipal.h"
 
 namespace mozilla {
@@ -42,6 +43,19 @@ nsresult BounceTrackingStateGlobal::RecordUserActivation(
              __FUNCTION__, PromiseFlatCString(aSiteHost).get()));
   }
 
+  // Make sure we don't overwrite an existing, more recent user activation. This
+  // is only relevant for callers that pass in a timestamp that isn't PR_Now(),
+  // e.g. when importing user activation data.
+  Maybe<PRTime> existingUserActivation = mUserActivation.MaybeGet(aSiteHost);
+  if (existingUserActivation.isSome() &&
+      existingUserActivation.value() >= aTime) {
+    MOZ_LOG(gBounceTrackingProtectionLog, LogLevel::Debug,
+            ("%s: Skip: A more recent user activation "
+             "already exists for %s",
+             __FUNCTION__, PromiseFlatCString(aSiteHost).get()));
+    return NS_OK;
+  }
+
   mUserActivation.InsertOrUpdate(aSiteHost, aTime);
 
   if (aSkipStorage || !ShouldPersistToDisk()) {