diff --git a/testing/web-platform/meta/media-source/mediasource-config-change-webm-a-bitrate.html.ini b/testing/web-platform/meta/media-source/mediasource-config-change-webm-a-bitrate.html.ini
new file mode 100644
index 000000000000..842de5026229
--- /dev/null
+++ b/testing/web-platform/meta/media-source/mediasource-config-change-webm-a-bitrate.html.ini
@@ -0,0 +1,3 @@
+[mediasource-config-change-webm-a-bitrate.html]
+  type: testharness
+  disabled: https://bugzilla.mozilla.org/show_bug.cgi?id=1134888