diff --git a/layout/generic/nsFrame.cpp b/layout/generic/nsFrame.cpp
index 4b0c016d679..e3c57d44a73 100644
--- a/layout/generic/nsFrame.cpp
+++ b/layout/generic/nsFrame.cpp
@@ -1683,6 +1683,14 @@ WrapPreserve3DListInternal(nsIFrame* aFrame, nsDisplayListBuilder *aBuilder, nsD
if (!aTemp->IsEmpty()) {
aOutput->AppendToTop(new (aBuilder) nsDisplayTransform(aBuilder, aFrame, aTemp, aIndex++));
}
+ // Override item's clipping with our current clip state (if any). Since we're
+ // bubbling up a preserve-3d transformed child to a preserve-3d parent,
+ // we can be sure the child doesn't have clip state of its own.
+ NS_ASSERTION(!item->GetClip().HasClip(), "Unexpected clip on item");
+ const DisplayItemClip* clip = aBuilder->ClipState().GetCurrentCombinedClip(aBuilder);
+ if (clip) {
+ item->SetClip(aBuilder, *clip);
+ }
aOutput->AppendToTop(item);
break;
}
diff --git a/layout/reftests/bugs/906199-1-ref.html b/layout/reftests/bugs/906199-1-ref.html
new file mode 100644
index 00000000000..c494dce827d
--- /dev/null
+++ b/layout/reftests/bugs/906199-1-ref.html
@@ -0,0 +1,32 @@
+
+
+
+
+
+
+
+
+
+
diff --git a/layout/reftests/bugs/906199-1.html b/layout/reftests/bugs/906199-1.html
new file mode 100644
index 00000000000..98f4548a790
--- /dev/null
+++ b/layout/reftests/bugs/906199-1.html
@@ -0,0 +1,33 @@
+
+
+
+
+
+
+
+
+
+
diff --git a/layout/reftests/bugs/reftest.list b/layout/reftests/bugs/reftest.list
index 7cf9e9b396a..c6f25a93eb3 100644
--- a/layout/reftests/bugs/reftest.list
+++ b/layout/reftests/bugs/reftest.list
@@ -1772,3 +1772,4 @@ test-pref(layout.css.flexbox.enabled,true) == 849407-1.html 849407-1-ref.html
== 883987-1f.html 883987-1-ref.html
== 890495-1.html 890495-1-ref.html
== 894931-1.html 894931-1-ref.html
+== 906199-1.html 906199-1-ref.html