--- a/devtools/shared/event-emitter.js
+++ b/devtools/shared/event-emitter.js
@@ -258,17 +258,17 @@ class EventEmitter {
 
 module.exports = EventEmitter;
 
 const isEventHandler = (listener) =>
   listener && handler in listener && typeof listener[handler] === "function";
 
 const Services = require("Services");
 const { describeNthCaller } = require("devtools/shared/platform/stack");
-let loggingEnabled = true;
+let loggingEnabled = false;
 
 if (!isWorker) {
   loggingEnabled = Services.prefs.getBoolPref("devtools.dump.emit");
   Services.prefs.addObserver("devtools.dump.emit", {
     observe: () => {
       loggingEnabled = Services.prefs.getBoolPref("devtools.dump.emit");
     }
   });

--- a/devtools/shared/old-event-emitter.js
+++ b/devtools/shared/old-event-emitter.js
@@ -2,17 +2,17 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 "use strict";
 
 const Services = require("Services");
 const defer = require("devtools/shared/defer");
 const { describeNthCaller } = require("devtools/shared/platform/stack");
-let loggingEnabled = true;
+let loggingEnabled = false;
 
 if (!isWorker) {
   loggingEnabled = Services.prefs.getBoolPref("devtools.dump.emit");
   Services.prefs.addObserver("devtools.dump.emit", {
     observe: () => {
       loggingEnabled = Services.prefs.getBoolPref("devtools.dump.emit");
     }
   });