diff --git a/dom/media/test/bug580982.webm b/dom/media/test/bug1377278.webm
similarity index 100%
rename from dom/media/test/bug580982.webm
rename to dom/media/test/bug1377278.webm
diff --git a/dom/media/test/bug580982.webm^headers^ b/dom/media/test/bug1377278.webm^headers^
similarity index 100%
rename from dom/media/test/bug580982.webm^headers^
rename to dom/media/test/bug1377278.webm^headers^
diff --git a/dom/media/test/manifest.js b/dom/media/test/manifest.js
index c6d533c1b8..7e30cc97d5 100644
--- a/dom/media/test/manifest.js
+++ b/dom/media/test/manifest.js
@@ -224,6 +224,9 @@ var gPlayTests = [
   // Test playback of a webm file
   { name:"seek-short.webm", type:"video/webm", duration:0.23 },
 
+  // Test playback of a webm file with 'matroska' doctype
+  { name:"bug1377278.webm", type:"video/webm", duration:4.0 },
+
   // Test playback of a WebM file with non-zero start time.
   { name:"split.webm", type:"video/webm", duration:1.967 },
 
@@ -532,7 +535,6 @@ var gErrorTests = [
   { name:"448636.ogv", type:"video/ogg" },
   { name:"bug504843.ogv", type:"video/ogg" },
   { name:"bug501279.ogg", type:"audio/ogg" },
-  { name:"bug580982.webm", type:"video/webm" },
   { name:"bug603918.webm", type:"video/webm" },
   { name:"bug604067.webm", type:"video/webm" },
   { name:"bogus.duh", type:"bogus/duh" }
diff --git a/dom/media/test/mochitest.ini b/dom/media/test/mochitest.ini
index ddabf78b66..742ac1b1c5 100644
--- a/dom/media/test/mochitest.ini
+++ b/dom/media/test/mochitest.ini
@@ -382,8 +382,6 @@ support-files =
   bug556821.ogv^headers^
   bug557094.ogv
   bug557094.ogv^headers^
-  bug580982.webm
-  bug580982.webm^headers^
   bug603918.webm
   bug603918.webm^headers^
   bug604067.webm
@@ -395,6 +393,8 @@ support-files =
   bug1301226.wav^headers^
   bug1301226-odd.wav
   bug1301226-odd.wav^headers^
+  bug1377278.webm
+  bug1377278.webm^headers^
   can_play_type_dash.js
   can_play_type_ogg.js
   can_play_type_wave.js