diff --git a/layout/reftests/css-visited/white-to-transparent-1-ref.html b/layout/reftests/css-visited/white-to-transparent-1-ref.html
new file mode 100644
index 000000000000..9ec44c5cd3e4
--- /dev/null
+++ b/layout/reftests/css-visited/white-to-transparent-1-ref.html
@@ -0,0 +1,11 @@
+
+Test for privacy restrictions on :visited (Bug 147777)
+
+unvisited
+visited
diff --git a/layout/reftests/css-visited/white-to-transparent-1.html b/layout/reftests/css-visited/white-to-transparent-1.html
new file mode 100644
index 000000000000..a9ac2695745d
--- /dev/null
+++ b/layout/reftests/css-visited/white-to-transparent-1.html
@@ -0,0 +1,13 @@
+
+Test for privacy restrictions on :visited (Bug 147777)
+
+unvisited
+visited
diff --git a/layout/style/nsStyleContext.cpp b/layout/style/nsStyleContext.cpp
index daa857847284..4027ccc0401e 100644
--- a/layout/style/nsStyleContext.cpp
+++ b/layout/style/nsStyleContext.cpp
@@ -753,6 +753,14 @@ nsStyleContext::GetVisitedDependentColor(nsCSSProperty aProperty)
/* static */ nscolor
nsStyleContext::CombineVisitedColors(nscolor *aColors, PRBool aLinkIsVisited)
{
+ if (NS_GET_A(aColors[1]) == 0) {
+ // If the style-if-visited is transparent, then just use the
+ // unvisited style rather than using the (meaningless) color
+ // components of the visited style along with a potentially
+ // non-transparent alpha value.
+ aLinkIsVisited = PR_FALSE;
+ }
+
// NOTE: We want this code to have as little timing dependence as
// possible on whether this->RelevantLinkVisited() is true.
const ColorIndexSet &set =
diff --git a/layout/style/test/test_visited_reftests.html b/layout/style/test/test_visited_reftests.html
index 1fa3a6d19d65..88ca19757778 100644
--- a/layout/style/test/test_visited_reftests.html
+++ b/layout/style/test/test_visited_reftests.html
@@ -77,6 +77,7 @@ var gTests = [
// FIXME: commented out because dynamic changes on the non-first-line
// part of the test don't work right when the link becomes visited.
//"== first-line-1.html first-line-1-ref.html",
+ "== white-to-transparent-1.html white-to-transparent-1-ref.html",
];
// Maintain a reference count of how many things we're waiting for until