--- a/devtools/client/webconsole/new-console-output/components/Message.js
+++ b/devtools/client/webconsole/new-console-output/components/Message.js
@@ -9,17 +9,17 @@
 // React & Redux
 const { Component, createFactory } = require("devtools/client/shared/vendor/react");
 const dom = require("devtools/client/shared/vendor/react-dom-factories");
 const PropTypes = require("devtools/client/shared/vendor/react-prop-types");
 const { l10n } =
   require("devtools/client/webconsole/new-console-output/utils/messages");
 const actions =
   require("devtools/client/webconsole/new-console-output/actions/index");
-const { MESSAGE_SOURCE } =
+const { MESSAGE_SOURCE, MESSAGE_TYPE } =
   require("devtools/client/webconsole/new-console-output/constants");
 const CollapseButton =
   require("devtools/client/webconsole/new-console-output/components/CollapseButton");
 const { MessageIndent } =
   require("devtools/client/webconsole/new-console-output/components/MessageIndent");
 const MessageIcon =
   require("devtools/client/webconsole/new-console-output/components/MessageIcon");
 const MessageRepeat =
@@ -240,17 +240,18 @@ class Message extends Component {
 
     const bodyElements = Array.isArray(messageBody) ? messageBody : [messageBody];
 
     return dom.div({
       className: topLevelClasses.join(" "),
       onContextMenu: this.onContextMenu,
       ref: node => {
         this.messageNode = node;
-      }
+      },
+      "aria-live": type === MESSAGE_TYPE.COMMAND ? "off" : "polite"
     },
       timestampEl,
       MessageIndent({indent}),
       icon,
       collapse,
       dom.span({ className: "message-body-wrapper" },
         dom.span({ className: "message-flex-body" },
           // Add whitespaces for formatting when copying to the clipboard.