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 eee0a4850ce..e6786d37582 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
@@ -14,7 +14,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="green" fill="remove"
+      values="green"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
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 59f61b12cfe..910b4ddc2b2 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
@@ -15,7 +15,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="green" fill="remove"
+      values="green"
       begin="a.begin+0.5s" dur="1s"/>
   </rect>
 </svg>
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 6b7cc036ea4..7b9f3ab03da 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
@@ -15,7 +15,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="green" fill="remove"
+      values="green"
       begin="a.begin+0.5s" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-resolved-1.svg b/layout/reftests/svg/smil/syncbase/changed-interval-resolved-1.svg
index a7563f7de7b..7a415ccdb92 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-resolved-1.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-resolved-1.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="10s; b.begin" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
     <set attributeName="y" begin="1s" id="b" to="0" fill="freeze"/>
   </rect>
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-resolved-2.svg b/layout/reftests/svg/smil/syncbase/changed-interval-resolved-2.svg
index 3d5fe219bc2..7d6a21adad5 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-resolved-2.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-resolved-2.svg
@@ -13,7 +13,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="10s; b.begin" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
     <set attributeName="y" begin="1s" id="c" to="0" fill="freeze"/>
   </rect>
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-simple-1.svg b/layout/reftests/svg/smil/syncbase/changed-interval-simple-1.svg
index 69862a15151..75268cb83bc 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-simple-1.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-simple-1.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 1s" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.end" dur="2s"/>
   </rect>
 </svg>
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 9c5c5210b96..3ca0d5691bb 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-simple-2.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-simple-2.svg
@@ -14,7 +14,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="10s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
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 d13fe6b8cf9..25bb109b2cd 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-simple-3.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-simple-3.svg
@@ -14,7 +14,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.end" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-simple-4.svg b/layout/reftests/svg/smil/syncbase/changed-interval-simple-4.svg
index 5c18503e968..3a47cd65551 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-simple-4.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-simple-4.svg
@@ -12,7 +12,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 1.5s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.end; a.end-0.5s" dur="2s" restart="whenNotActive"/>
   </rect>
 </svg>
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 ff6121993d5..3d4253784ee 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-simple-5.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-simple-5.svg
@@ -14,7 +14,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/changed-interval-sort-1.svg b/layout/reftests/svg/smil/syncbase/changed-interval-sort-1.svg
index a31aaf5c7f5..a422b1196f9 100644
--- a/layout/reftests/svg/smil/syncbase/changed-interval-sort-1.svg
+++ b/layout/reftests/svg/smil/syncbase/changed-interval-sort-1.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 1s" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="3s; a.end" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cross-container-1.xhtml b/layout/reftests/svg/smil/syncbase/cross-container-1.xhtml
index c54a156ce5d..72d7eb782e2 100644
--- a/layout/reftests/svg/smil/syncbase/cross-container-1.xhtml
+++ b/layout/reftests/svg/smil/syncbase/cross-container-1.xhtml
@@ -22,7 +22,7 @@ function snapshot() {
 <svg xmlns="http://www.w3.org/2000/svg" width="120px" height="120px" id="svg-a">
   <rect width="100" height="100" fill="red">
     <animate attributeName="fill" attributeType="CSS" id="a"
-      values="orange; green; purple" fill="remove" calcMode="discrete"
+      values="orange; green; purple" calcMode="discrete"
       begin="b.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cross-container-3.xhtml b/layout/reftests/svg/smil/syncbase/cross-container-3.xhtml
index c6d4a18122c..9c41142d29a 100644
--- a/layout/reftests/svg/smil/syncbase/cross-container-3.xhtml
+++ b/layout/reftests/svg/smil/syncbase/cross-container-3.xhtml
@@ -48,7 +48,7 @@ function snapshotB() {
 <svg xmlns="http://www.w3.org/2000/svg" width="120px" height="120px" id="svg-a">
   <rect width="100" height="100" fill="orange">
     <animate attributeName="fill" attributeType="CSS" id="a"
-      values="green; red" fill="remove"
+      values="green; red"
       begin="b.begin" dur="0.5s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-change-1.svg b/layout/reftests/svg/smil/syncbase/cycle-change-1.svg
index 34d1469962c..d9bcab49842 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-change-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-change-1.svg
@@ -13,7 +13,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="b.begin; 3s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-change-2.svg b/layout/reftests/svg/smil/syncbase/cycle-change-2.svg
index 98e643697b6..2c7f059a8c5 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-change-2.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-change-2.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="b.begin; 0s; 1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-delete-1.svg b/layout/reftests/svg/smil/syncbase/cycle-delete-1.svg
index 4b9929760b2..537db186b64 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-delete-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-delete-1.svg
@@ -13,7 +13,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="b.begin; 1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-invalid-1.svg b/layout/reftests/svg/smil/syncbase/cycle-invalid-1.svg
index 0735d24acad..4db735e647c 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-invalid-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-invalid-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="b.begin" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="red" fill="remove"
+      values="red"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-invalid-2.svg b/layout/reftests/svg/smil/syncbase/cycle-invalid-2.svg
index 2abb3f5bb4a..6a1306ad852 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-invalid-2.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-invalid-2.svg
@@ -12,7 +12,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="b"
       begin="a.begin" dur="3s"/>
     <animate attributeName="fill" attributeType="CSS" id="c"
-      values="green; red" fill="remove"
+      values="green; red"
       begin="0" end="b.end"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-invalid-3.svg b/layout/reftests/svg/smil/syncbase/cycle-invalid-3.svg
index b60aa8de07e..05c2cea7224 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-invalid-3.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-invalid-3.svg
@@ -45,9 +45,9 @@
    -->
   <rect y="100" width="100" height="100" fill="red">
     <animate attributeName="y" attributeType="XML" from="-50" to="50" id="a"
-      begin="5s; b.begin-1s" dur="2s" fill="remove"/>
+      begin="5s; b.begin-1s" dur="2s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="green; orange" fill="remove"
+      values="green; orange"
       begin="a.begin-1s" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-invalid-4.svg b/layout/reftests/svg/smil/syncbase/cycle-invalid-4.svg
index 74450f5272c..0ceae28bc71 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-invalid-4.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-invalid-4.svg
@@ -26,7 +26,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="b.begin; 0s" dur="1.5s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="a.end" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-ok-1.svg b/layout/reftests/svg/smil/syncbase/cycle-ok-1.svg
index ad30a989296..6add77fb440 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-ok-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-ok-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="b.begin; 1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-ok-2.svg b/layout/reftests/svg/smil/syncbase/cycle-ok-2.svg
index 4d3fe54d2dd..a7e63c6c842 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-ok-2.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-ok-2.svg
@@ -13,7 +13,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="b.begin+1s" dur="1s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="0s; a.begin+0.5s" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-ok-3.svg b/layout/reftests/svg/smil/syncbase/cycle-ok-3.svg
index ca5bcc624d1..5e4f006fac0 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-ok-3.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-ok-3.svg
@@ -27,7 +27,7 @@
       values="orange; green; orange"
       begin="a.begin" dur="2s"/>
     <animate attributeName="fill" attributeType="CSS" id="c"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="0" end="b.end"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-ok-4.svg b/layout/reftests/svg/smil/syncbase/cycle-ok-4.svg
index 07382e34da0..a7fa7d8c1b4 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-ok-4.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-ok-4.svg
@@ -14,7 +14,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="b.begin; 0s" dur="1.5s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.end" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-ok-5.svg b/layout/reftests/svg/smil/syncbase/cycle-ok-5.svg
index e4b45ff4375..d2a9a5e194e 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-ok-5.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-ok-5.svg
@@ -14,7 +14,7 @@
   <rect y="100" width="100" height="100" fill="red">
     <animate id="a1" attributeName="y" attributeType="XML"
       from="-20" to="80" dur="10s"
-      end="a1.begin+6s" max="2.5s" fill="remove" />
+      end="a1.begin+6s" max="2.5s" />
     <animate attributeName="fill" attributeType="CSS"
       values="orange; green; orange" keyTimes="0; 0.1; 1" dur="10s"
       begin="1s" end="a1.end+6s"
diff --git a/layout/reftests/svg/smil/syncbase/cycle-recursion-1.svg b/layout/reftests/svg/smil/syncbase/cycle-recursion-1.svg
index d046eda389d..1038e739348 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-recursion-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-recursion-1.svg
@@ -32,7 +32,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="c.end" dur="0.5s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="green; blue" fill="remove"
+      values="green; blue"
       begin="a.begin" dur="1s" additive="replace"/>
     <animate attributeName="x" attributeType="XML" id="c"
       from="0" to="100" fill="freeze"
diff --git a/layout/reftests/svg/smil/syncbase/cycle-recursion-2.svg b/layout/reftests/svg/smil/syncbase/cycle-recursion-2.svg
index a71d93dbf94..df859a5305e 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-recursion-2.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-recursion-2.svg
@@ -9,9 +9,9 @@
    -->
   <rect width="100" height="100" fill="green">
     <animate attributeName="y" attributeType="XML" from="100" to="100" id="a"
-      begin="20h; b.begin-1s" dur="4s" fill="remove"/>
+      begin="20h; b.begin-1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="a.begin-1s" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-self-ref-1.svg b/layout/reftests/svg/smil/syncbase/cycle-self-ref-1.svg
index c672251b2fe..52bb8bba9f1 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-self-ref-1.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-self-ref-1.svg
@@ -8,7 +8,7 @@
    -->
   <rect width="100" height="100" fill="red">
     <animate attributeName="fill" attributeType="CSS" id="a"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin+1.5s; -0.5s" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-self-ref-2.svg b/layout/reftests/svg/smil/syncbase/cycle-self-ref-2.svg
index 6b0b9c49461..215dc6098b0 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-self-ref-2.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-self-ref-2.svg
@@ -8,7 +8,7 @@
    -->
   <rect width="100" height="100" fill="red">
     <animate attributeName="fill" attributeType="CSS" id="a"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.end; -1s" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/cycle-self-ref-3.svg b/layout/reftests/svg/smil/syncbase/cycle-self-ref-3.svg
index e2097ea16e3..50fdaf97393 100644
--- a/layout/reftests/svg/smil/syncbase/cycle-self-ref-3.svg
+++ b/layout/reftests/svg/smil/syncbase/cycle-self-ref-3.svg
@@ -13,7 +13,7 @@
    -->
   <rect width="100" height="100" fill="red">
     <animate attributeName="fill" attributeType="CSS" id="a"
-      values="orange; green; blue; yellow; purple" fill="remove"
+      values="orange; green; blue; yellow; purple"
       begin="a.end; -1s" end="a.begin+2s" dur="4s"/>
   </rect>
 </svg>
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 cc06556d05f..a5e01b8ee42 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-1.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-1.svg
@@ -15,7 +15,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="10s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
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 e0ba4f99f0a..cc2fb75d923 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-2.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-2.svg
@@ -20,7 +20,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 1s" dur="0.1s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="-1.5s; a.begin" dur="2s" restart="whenNotActive"/>
   </rect>
 </svg>
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 f1c155bd092..5e8f1b34ed9 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-3.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-3.svg
@@ -14,7 +14,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 1s" dur="0.1s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="-1.5s; a.begin" dur="2s" restart="whenNotActive"/>
   </rect>
 </svg>
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 b2a533e8b8b..26e74e04ed0 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-4.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-4.svg
@@ -19,7 +19,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="b"
       begin="1s" end="a.begin" dur="3s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="b.begin" dur="2s"/>
   </rect>
 </svg>
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 6dc9ae0d385..4e703cb31de 100644
--- a/layout/reftests/svg/smil/syncbase/deleted-interval-simple-5.svg
+++ b/layout/reftests/svg/smil/syncbase/deleted-interval-simple-5.svg
@@ -14,7 +14,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s" dur="1s"/>
     <animate attributeName="fill" attributeType="CSS" id="b"
-      values="red; red" fill="remove"
+      values="red; red"
       begin="a.end" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-chain-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-chain-1.svg
index bf8d6c3d184..e90b4f9c9b7 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-chain-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-chain-1.svg
@@ -16,7 +16,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="d"
       begin="c.begin+0.5s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; blue" fill="remove"
+      values="orange; green; blue"
       begin="d.begin; a.begin" dur="5s" restart="whenNotActive"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-chain-2.svg b/layout/reftests/svg/smil/syncbase/new-interval-chain-2.svg
index 19d374f1a4e..e883fea0834 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-chain-2.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-chain-2.svg
@@ -16,7 +16,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="d"
       begin="c.begin+0.5s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; blue" fill="remove"
+      values="orange; green; blue"
       begin="d.begin; a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-1.svg
index e408c9ad6a7..54461d56164 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin+0.5s; a.begin" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-2.svg b/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-2.svg
index f1c1788c3d9..7312af00094 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-2.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-2.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin; a.begin+0.5s" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-3.svg b/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-3.svg
index 860c9c8c46d..d3ba9fdf924 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-3.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-doubly-dependent-3.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin+0.5s; a.begin" dur="2s" restart="whenNotActive"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-early-end-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-early-end-1.svg
index e91ebbfb982..c166a8bcbb2 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-early-end-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-early-end-1.svg
@@ -12,7 +12,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 2s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin-0.5s" dur="1s" restart="whenNotActive"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-early-end-2.svg b/layout/reftests/svg/smil/syncbase/new-interval-early-end-2.svg
index d437dfc1e41..aa9845def53 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-early-end-2.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-early-end-2.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 1.5s" dur="1s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin+0.25s; a.begin" dur="1s" restart="whenNotActive"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-early-end-3.svg b/layout/reftests/svg/smil/syncbase/new-interval-early-end-3.svg
index 7248835afe0..e506d03c470 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-early-end-3.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-early-end-3.svg
@@ -12,7 +12,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 1.75s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; blue" fill="remove"
+      values="orange; green; blue"
       begin="a.begin-0.25s; a.begin" dur="1s" restart="whenNotActive"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-early-end-4.svg b/layout/reftests/svg/smil/syncbase/new-interval-early-end-4.svg
index fda6a69c1b8..dd3ad2644d5 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-early-end-4.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-early-end-4.svg
@@ -14,7 +14,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s; 1.5s" dur="1s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin-0.25s; a.begin" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-early-end-5.svg b/layout/reftests/svg/smil/syncbase/new-interval-early-end-5.svg
index cb7fb39dc88..a48bf497b99 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-early-end-5.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-early-end-5.svg
@@ -13,7 +13,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0.5s; 1.5s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="0.75s; 1.5s; a.begin-0.5s" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-early-end-6.svg b/layout/reftests/svg/smil/syncbase/new-interval-early-end-6.svg
index 87d42284cfa..cf283c71142 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-early-end-6.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-early-end-6.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0.5s; 1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="0.5s; 1s; a.begin+0.5s" dur="1s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-end-dep-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-end-dep-1.svg
index 5495f4a1e6f..c81bda542b8 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-end-dep-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-end-dep-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0s" dur="1s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.end" dur="2s"/>
   </rect>
 </svg>
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 39e2a0a4e35..9a2027d3a18 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
@@ -24,7 +24,7 @@
   <rect width="100" height="100" fill="red">
     <set attributeName="y" attributeType="XML" to="0" id="a" begin="2s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; purple" fill="remove"
+      values="orange; green; purple"
       begin="a.begin-1s" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-1.svg
index c280b192fa1..7832e2b09d4 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin-0.5s" dur="3s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-2.svg b/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-2.svg
index 446fe7e69a0..e06b9607d8a 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-2.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-2.svg
@@ -24,7 +24,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="3s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="green; orange" fill="remove"
+      values="green; orange"
       begin="a.begin-1s" dur="3s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-3.svg b/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-3.svg
index f1ad8ab7e6a..425f1196764 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-3.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-3.svg
@@ -12,7 +12,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin-3s" dur="8s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-4.svg b/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-4.svg
index 5171b944712..62bcb8e6ba5 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-4.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-negative-offset-4.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="2s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin-2s" dur="4s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-negative-syncbase-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-negative-syncbase-1.svg
index 0f981cc6714..8e80f799200 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-negative-syncbase-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-negative-syncbase-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="-1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin-1s" dur="8s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-restart-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-restart-1.svg
index c270446d413..b33ecddc0df 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-restart-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-restart-1.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="0.5s; 1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-restart-2.svg b/layout/reftests/svg/smil/syncbase/new-interval-restart-2.svg
index ef00f9b0ec1..d27843b89d3 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-restart-2.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-restart-2.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s; 1.5s" dur="4s" restart="whenNotActive"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-restart-3.svg b/layout/reftests/svg/smil/syncbase/new-interval-restart-3.svg
index 27821a43baa..ec8429dfc06 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-restart-3.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-restart-3.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s; 1.5s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s" restart="whenNotActive"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-sample-order-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-sample-order-1.svg
index bc93f95d295..7cc1abce457 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-sample-order-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-sample-order-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="-3s; 1.5s" dur="20s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin-0.5s; 1.5s" dur="2s" restart="whenNotActive"/>
     <!--
       So initially we have:
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-simple-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-simple-1.svg
index f4f68aa8f78..9d9a1807390 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-simple-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-simple-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-simple-2.svg b/layout/reftests/svg/smil/syncbase/new-interval-simple-2.svg
index 02df10dac5b..6465845f7f3 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-simple-2.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-simple-2.svg
@@ -9,7 +9,7 @@
    -->
   <rect width="100" height="100" fill="red">
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin" dur="2s"/>
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-triply-dependent-1.svg b/layout/reftests/svg/smil/syncbase/new-interval-triply-dependent-1.svg
index 3e360083af0..93b8159c6bf 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-triply-dependent-1.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-triply-dependent-1.svg
@@ -10,7 +10,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin; a.begin; a.begin" dur="2s"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/syncbase/new-interval-triply-dependent-2.svg b/layout/reftests/svg/smil/syncbase/new-interval-triply-dependent-2.svg
index f5ece6d1561..89fa4ec8b55 100644
--- a/layout/reftests/svg/smil/syncbase/new-interval-triply-dependent-2.svg
+++ b/layout/reftests/svg/smil/syncbase/new-interval-triply-dependent-2.svg
@@ -11,7 +11,7 @@
     <animate attributeName="y" attributeType="XML" from="0" to="0" id="a"
       begin="1s" dur="4s"/>
     <animate attributeName="fill" attributeType="CSS"
-      values="orange; green; orange" fill="remove"
+      values="orange; green; orange"
       begin="a.begin-0.5s; a.begin+0.5s; a.begin" dur="1s"/>
   </rect>
 </svg>