diff --git a/dom/media/test/mochitest.ini b/dom/media/test/mochitest.ini
index 1f5c687f9e8..ceb57b0e35f 100644
--- a/dom/media/test/mochitest.ini
+++ b/dom/media/test/mochitest.ini
@@ -400,6 +400,7 @@ skip-if = toolkit == 'android' # bug 1043403
 [test_eme_requestKeySystemAccess.html]
 skip-if = toolkit == 'android' # bug 1043403
 [test_eme_stream_capture_blocked.html]
+tags=msg
 skip-if = toolkit == 'android' || (os == 'win' && !debug) # bug 1043403, bug 1140675
 [test_empty_resource.html]
 [test_error_in_video_document.html]
@@ -427,31 +428,51 @@ skip-if = (toolkit == 'android' && processor == 'x86') #x86 only bug 914439
 [test_media_sniffer.html]
 skip-if = (toolkit == 'android' && processor == 'x86') #x86 only bug 914439
 [test_mediarecorder_avoid_recursion.html]
+tags=msg
 [test_mediarecorder_creation.html]
+tags=msg
 [test_mediarecorder_creation_fail.html]
+tags=msg
 [test_mediarecorder_getencodeddata.html]
+tags=msg
 [test_mediarecorder_record_4ch_audiocontext.html]
+tags=msg
 [test_mediarecorder_record_audiocontext.html]
+tags=msg
 [test_mediarecorder_record_audiocontext_mlk.html]
+tags=msg
 [test_mediarecorder_record_audionode.html]
+tags=msg
 [test_mediarecorder_record_gum_video_timeslice.html]
+tags=msg
 skip-if = buildapp == 'b2g' || toolkit == 'android' # mimetype check, bug 969289
 [test_mediarecorder_record_immediate_stop.html]
+tags=msg
 [test_mediarecorder_record_no_timeslice.html]
+tags=msg
 skip-if = toolkit == 'gonk' && debug
 [test_mediarecorder_record_nosrc.html]
+tags=msg
 [test_mediarecorder_record_session.html]
+tags=msg
 [test_mediarecorder_record_startstopstart.html]
+tags=msg
 skip-if = toolkit == 'gonk' && debug
 [test_mediarecorder_record_stopms.html]
+tags=msg
 [test_mediarecorder_record_timeslice.html]
+tags=msg
 skip-if = toolkit == 'gonk' && debug
 [test_mediarecorder_reload_crash.html]
+tags=msg
 [test_mediarecorder_unsupported_src.html]
+tags=msg
 [test_mediarecorder_record_getdata_afterstart.html]
+tags=msg
 skip-if = toolkit == 'gonk' && debug
 [test_mediatrack_consuming_mediaresource.html]
 [test_mediatrack_consuming_mediastream.html]
+tags=msg
 [test_mediatrack_events.html]
 skip-if = toolkit == 'gonk' && debug # bug 1065924
 [test_mediatrack_parsing_ogg.html]
@@ -530,18 +551,27 @@ skip-if = (toolkit == 'android' && processor == 'x86') #timeout x86 only bug 914
 [test_standalone.html]
 skip-if = (toolkit == 'android' && processor == 'x86') #x86 only bug 914439
 [test_streams_autoplay.html]
+tags=msg
 [test_streams_element_capture.html]
 #x86 only bug 914439, b2g desktop bug 752796
 skip-if = (toolkit == 'android' && processor == 'x86') || (buildapp == 'b2g' && toolkit != 'gonk')
+tags=msg
 [test_streams_element_capture_createObjectURL.html]
 skip-if = (toolkit == 'android' && processor == 'x86') #x86 only bug 914439
+tags=msg
 [test_streams_element_capture_playback.html]
+tags=msg
 [test_streams_element_capture_reset.html]
+tags=msg
 [test_streams_gc.html]
 skip-if = buildapp == 'b2g' && toolkit != 'gonk' # bug 1096270
+tags=msg
 [test_streams_individual_pause.html]
+tags=msg
 [test_streams_srcObject.html]
+tags=msg
 [test_streams_tracks.html]
+tags=msg
 [test_texttrack.html]
 [test_texttrackcue.html]
 [test_texttracklist.html]
diff --git a/dom/media/tests/mochitest/identity/mochitest.ini b/dom/media/tests/mochitest/identity/mochitest.ini
index 6eb017db894..518329165d8 100644
--- a/dom/media/tests/mochitest/identity/mochitest.ini
+++ b/dom/media/tests/mochitest/identity/mochitest.ini
@@ -6,6 +6,7 @@ skip-if = (os == 'win' && strictContentSandbox) || android_version == '10' || an
 support-files =
   /.well-known/idp-proxy/idp.js
   identityPcTest.js
+tags = msg
 
 [test_idpproxy.html]
 support-files =
diff --git a/dom/media/tests/mochitest/ipc/mochitest.ini b/dom/media/tests/mochitest/ipc/mochitest.ini
index 8ab30ed1cad..21a6d91a423 100644
--- a/dom/media/tests/mochitest/ipc/mochitest.ini
+++ b/dom/media/tests/mochitest/ipc/mochitest.ini
@@ -1,4 +1,5 @@
 [DEFAULT]
+tags=msg
 support-files =
   ipc.json
 
diff --git a/dom/media/tests/mochitest/mochitest.ini b/dom/media/tests/mochitest/mochitest.ini
index 7611bb85962..b6a7d395d02 100644
--- a/dom/media/tests/mochitest/mochitest.ini
+++ b/dom/media/tests/mochitest/mochitest.ini
@@ -1,5 +1,6 @@
 [DEFAULT]
 # strictContentSandbox - bug 1042735, Android 2.3 - bug 981881
+tags=msg
 skip-if = (os == 'win' && strictContentSandbox) || android_version == '10' || android_version == '18' || (buildapp == 'mulet')
 support-files =
   head.js
diff --git a/dom/media/webaudio/test/blink/mochitest.ini b/dom/media/webaudio/test/blink/mochitest.ini
index b5937601ee0..7ce24cfa1cc 100644
--- a/dom/media/webaudio/test/blink/mochitest.ini
+++ b/dom/media/webaudio/test/blink/mochitest.ini
@@ -1,4 +1,5 @@
 [DEFAULT]
+tags=msg
 support-files =
   audio-testing.js
   convolution-testing.js
diff --git a/dom/media/webaudio/test/mochitest.ini b/dom/media/webaudio/test/mochitest.ini
index a0bf9dace4b..bc930563746 100644
--- a/dom/media/webaudio/test/mochitest.ini
+++ b/dom/media/webaudio/test/mochitest.ini
@@ -1,4 +1,5 @@
 [DEFAULT]
+tags=msg
 skip-if = ((buildapp == 'mulet' || buildapp == 'b2g') && (toolkit != 'gonk' || debug)) || (os == 'win' && strictContentSandbox) #b2g-debug,b2g-desktop(bug 916135); strictContentSandbox(Bug 1042735)
 support-files =
   audio-expected.wav
diff --git a/dom/media/webspeech/recognition/test/mochitest.ini b/dom/media/webspeech/recognition/test/mochitest.ini
index 22e85d3280e..467528163cb 100644
--- a/dom/media/webspeech/recognition/test/mochitest.ini
+++ b/dom/media/webspeech/recognition/test/mochitest.ini
@@ -1,4 +1,5 @@
 [DEFAULT]
+tags=msg
 support-files =
   head.js
   hello.ogg
diff --git a/dom/media/webspeech/synth/test/mochitest.ini b/dom/media/webspeech/synth/test/mochitest.ini
index 74d6ebb41f4..7ff189dd923 100644
--- a/dom/media/webspeech/synth/test/mochitest.ini
+++ b/dom/media/webspeech/synth/test/mochitest.ini
@@ -1,4 +1,5 @@
 [DEFAULT]
+tags=msg
 support-files =
   common.js
   file_setup.html