--- a/layout/style/test/test_transitions_per_property.html
+++ b/layout/style/test/test_transitions_per_property.html
@@ -58,21 +58,19 @@ function any_unit_to_num(str)
 var FUNC_NEGATIVE = "cubic-bezier(0.25, -2, 0.75, 1)";
 var FUNC_OVERONE = "cubic-bezier(0.25, 0, 0.75, 3)";
 
 // After resolving Bug 1387080, we can remove this variable.
 const isServo = SpecialPowers.DOMWindowUtils.isStyledByServo;
 
 // The following properties will be skipped while using Servo backend.
 var skippedProperties = {
-    "box-shadow": true,             // Bug 1387973
     "stroke-dasharray": true,       // Bug 1387986
     "stroke-dashoffset": true,      // Bug 1369614
     "stroke-width": true,           // Bug 1369614
-    "text-shadow": true,            // Bug 1387973
 };
 
 var supported_properties = {
     "border-bottom-left-radius": [ test_radius_transition ],
     "border-bottom-right-radius": [ test_radius_transition ],
     "border-top-left-radius": [ test_radius_transition ],
     "border-top-right-radius": [ test_radius_transition ],
     "-moz-box-flex": [ test_float_zeroToOne_transition,
@@ -1677,20 +1675,38 @@ function test_shadow_transition(prop) {
     div.style.setProperty(prop, "8px 8px 8px red", "");
     is(cs.getPropertyValue(prop), "rgb(255, 0, 0) 8px 8px 8px 0px",
        "shadow-valued property " + prop + ": non-interpolable cases");
     check_distance(prop, "8px 8px 8px red inset",
                          "rgb(255, 0, 0) 8px 8px 8px 2px inset",
                          "8px 8px 8px 8px red inset");
   }
 
+  // Transition beween values with color and without color.
+  div.style.setProperty("transition-property", "none", "");
+  div.style.setProperty("color", "rgb(3, 0, 0)", "");
+  div.style.setProperty(prop, "2px 2px 2px", "");
+  is(cs.getPropertyValue(prop), "rgb(3, 0, 0) 2px 2px 2px" + spreadStr,
+     "shadow-valued property " + prop + ": computed value before transition");
+  div.style.setProperty("transition-property", prop, "");
+  div.style.setProperty(prop, "8px 8px 8px red", "");
+  // Bug 726550 for gecko (can't transition), bug 1390697 for servo (doesn't
+  // work currentColor animation for {text,box}-shadow).
+  todo_is(cs.getPropertyValue(prop),
+          "rgb(66, 0, 0) 3.5px 3.5px 3.5px" + spreadStr,
+          "shadow-valued property " + prop +
+          ": interpolation values with/without color");
+
+  // Transition beween values without color.
   var defaultColor = cs.getPropertyValue("color") + " ";
+  div.style.setProperty("transition-property", "none", "");
   div.style.setProperty(prop, "2px 2px 2px", "");
   is(cs.getPropertyValue(prop), defaultColor + "2px 2px 2px" + spreadStr,
-     "shadow-valued property " + prop + ": non-interpolable cases");
+     "shadow-valued property " + prop + ": computed value before transition");
+  div.style.setProperty("transition-property", prop, "");
   div.style.setProperty(prop, "6px 14px 10px", "");
   is(cs.getPropertyValue(prop), defaultColor + "3px 5px 4px" + spreadStr,
      "shadow-valued property " + prop + ": interpolation without color");
   check_distance(prop, "2px 2px 2px", "3px 5px 4px", "6px 14px 10px");
 
   div.style.setProperty("transition-timing-function", FUNC_NEGATIVE, "");
   div.style.setProperty("transition-property", "none", "");
   div.style.setProperty(prop, "0px 0px 0px black", "");