diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-1.svg b/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-1.svg
index e6786d375828..5952d9912534 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-1.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-1.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(1.5);
         document.getElementById('a').removeAttribute('begin');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Deleting the begin spec whilst the element is active should not cause
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-2.svg b/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-2.svg
index 910b4ddc2b23..c2db15647983 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-2.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-2.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(1.2);
         document.getElementById('a').removeAttribute('begin');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Deleting the begin spec whilst the syncbase element is active should not
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-3.svg b/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-3.svg
index 7b9f3ab03daf..103b0e780c6e 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-3.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-change-spec-3.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(1.2);
         document.getElementById('a').setAttribute('begin', '0s');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Changing the begin spec whilst the syncbase element is active should not
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-simple-2.svg b/layout/reftests/svg/smil/syncbase/changed-interval-simple-2.svg
index 3ca0d5691bb1..28a87e738583 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-simple-2.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-simple-2.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').beginElementAt(1);
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     We'll add another begin instance time at t=1s for 'a' by script, causing a
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-simple-3.svg b/layout/reftests/svg/smil/syncbase/changed-interval-simple-3.svg
index 25bb109b2cd3..80c945a084c1 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-simple-3.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-simple-3.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').endElementAt(1);
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     We'll add another end instance time at t=1s for a by script, causing a
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-simple-5.svg b/layout/reftests/svg/smil/syncbase/changed-interval-simple-5.svg
index 3d4253784eed..07648813c1ea 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-simple-5.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-simple-5.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').removeAttribute('begin');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Changing the begin attribute by script should cause a change notice to be
diff --git a/layout/reftests/svg/smil/syncbase/cycle-change-1.svg b/layout/reftests/svg/smil/syncbase/cycle-change-1.svg
index d9bcab498421..456a9237b4ff 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-change-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-change-1.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').beginElementAt(1);
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Test that cycles don't cause problems for change notices as well.
diff --git a/layout/reftests/svg/smil/syncbase/cycle-delete-1.svg b/layout/reftests/svg/smil/syncbase/cycle-delete-1.svg
index 537db186b642..79408a0483b7 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-delete-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-delete-1.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').setAttribute('end', '0s');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Test that cycles don't cause problems for deleted intervals.
diff --git a/layout/reftests/svg/smil/syncbase/cycle-invalid-4.svg b/layout/reftests/svg/smil/syncbase/cycle-invalid-4.svg
index 0ceae28bc71c..ddf489308d42 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-invalid-4.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-invalid-4.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').removeAttribute('dur');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     A cycle that is valid at first but then becomes invalid.
diff --git a/layout/reftests/svg/smil/syncbase/cycle-ok-3.svg b/layout/reftests/svg/smil/syncbase/cycle-ok-3.svg
index 5e4f006fac05..1594eecf05e1 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-ok-3.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-ok-3.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('c').setAttribute('dur', '1s');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Based on Example 2 from SMIL3, an invalid cycle, but made valid by a DOM
diff --git a/layout/reftests/svg/smil/syncbase/cycle-recursion-1.svg b/layout/reftests/svg/smil/syncbase/cycle-recursion-1.svg
index 1038e7393484..d78cd3f62ea8 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-recursion-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-recursion-1.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('c').removeAttribute('dur');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     At first we have:
diff --git a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-1.svg b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-1.svg
index a5e01b8ee420..cb516275a83e 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-1.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-1.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').setAttribute('end', '0s');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     A simple case of a deleting interval.
diff --git a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-2.svg b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-2.svg
index cc2fb75d9231..4b60ca66412a 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-2.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-2.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0.75);
         document.getElementById('a').setAttribute('restart', 'never');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     A simple case of a deleting interval.
diff --git a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-3.svg b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-3.svg
index 5e8f1b34ed98..7f290b8a0ccd 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-3.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-3.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0.25);
         document.getElementById('a').setAttribute('restart', 'never');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     As with deleted-interval-simple-2.svg but this time we should get the
diff --git a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-4.svg b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-4.svg
index 26e74e04ed06..7ec038ad7147 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-4.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-4.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').beginElementAt(0.5);
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     A simple case of a deleting interval.
diff --git a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-5.svg b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-5.svg
index 4e703cb31de0..677c960330a2 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-5.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-5.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(0);
         document.getElementById('a').removeAttribute('dur');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     A case of a changing interval that causes another interval to have an
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-freeze-begin-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-freeze-begin-1.svg
index 9a2027d3a186..07df8fc11163 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-freeze-begin-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-freeze-begin-1.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+        document.documentElement.pauseAnimations();
         document.documentElement.setCurrentTime(1.5);
         document.getElementById('a').setAttribute('begin', '3s');
-        setTimeAndSnapshot(2, true)">
+        setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Tests that when we create an interval we freeze the begin time once it has
diff --git a/layout/reftests/svg/smil/syncbase/sandwich-priority-10.svg b/layout/reftests/svg/smil/syncbase/sandwich-priority-10.svg
index 0aa536f0b809..d1d0f59475b9 100644
--- a/layout/reftests/svg/smil/syncbase/sandwich-priority-10.svg
+++ b/layout/reftests/svg/smil/syncbase/sandwich-priority-10.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+      document.documentElement.pauseAnimations();
       document.documentElement.setCurrentTime(0);
       document.getElementById('b').setAttribute('end', 'a.begin');
-      setTimeAndSnapshot(2, true)">
+      setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Test of animation sandwich priority based on syncbase dependencies.
diff --git a/layout/reftests/svg/smil/syncbase/sandwich-priority-8.svg b/layout/reftests/svg/smil/syncbase/sandwich-priority-8.svg
index beacc13810ef..9ff2588fb7f6 100644
--- a/layout/reftests/svg/smil/syncbase/sandwich-priority-8.svg
+++ b/layout/reftests/svg/smil/syncbase/sandwich-priority-8.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+      document.documentElement.pauseAnimations();
       document.documentElement.setCurrentTime(0);
       document.getElementById('b').setAttribute('begin', 'a.begin');
-      setTimeAndSnapshot(2, true)">
+      setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Test of animation sandwich priority based on syncbase dependencies.
diff --git a/layout/reftests/svg/smil/syncbase/sandwich-priority-9.svg b/layout/reftests/svg/smil/syncbase/sandwich-priority-9.svg
index d8b2498743ca..42417c028932 100644
--- a/layout/reftests/svg/smil/syncbase/sandwich-priority-9.svg
+++ b/layout/reftests/svg/smil/syncbase/sandwich-priority-9.svg
@@ -2,9 +2,10 @@
      xmlns:xlink="http://www.w3.org/1999/xlink"
      class="reftest-wait"
      onload="
+      document.documentElement.pauseAnimations();
       document.documentElement.setCurrentTime(0);
       document.getElementById('b').setAttribute('begin', 'a.begin');
-      setTimeAndSnapshot(2, true)">
+      setTimeAndSnapshot(2, false)">
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <!--
     Test of animation sandwich priority based on syncbase dependencies.