diff --git a/dom/media/webvtt/vtt.jsm b/dom/media/webvtt/vtt.jsm
index e724e8182c6e..8294a42b073d 100644
--- a/dom/media/webvtt/vtt.jsm
+++ b/dom/media/webvtt/vtt.jsm
@@ -96,9 +96,8 @@ this.EXPORTED_SYMBOLS = ["WebVTT"];
   }
 
   Settings.prototype = {
-    // Only accept the first assignment to any key.
     set: function(k, v) {
-      if (!this.get(k) && v !== "") {
+      if (v !== "") {
         this.values[k] = v;
       }
     },
diff --git a/testing/web-platform/meta/webvtt/webvtt-file-format-parsing/webvtt-file-parsing/001.html.ini b/testing/web-platform/meta/webvtt/webvtt-file-format-parsing/webvtt-file-parsing/001.html.ini
index 2d35dcd869fa..0e0e8a925108 100644
--- a/testing/web-platform/meta/webvtt/webvtt-file-format-parsing/webvtt-file-parsing/001.html.ini
+++ b/testing/web-platform/meta/webvtt/webvtt-file-format-parsing/webvtt-file-parsing/001.html.ini
@@ -3,18 +3,12 @@
   [WebVTT parser tests, settings-vertical.vtt]
     expected: FAIL
 
-  [WebVTT parser tests, settings-size.vtt]
-    expected: FAIL
-
   [WebVTT parser tests, settings-position.vtt]
     expected: FAIL
 
   [WebVTT parser tests, settings-line.vtt]
     expected: FAIL
 
-  [WebVTT parser tests, settings-align.vtt]
-    expected: FAIL
-
   [WebVTT parser tests, signature-space-no-newline.vtt]
     expected: FAIL