--- a/testing/geckodriver/src/prefs.rs
+++ b/testing/geckodriver/src/prefs.rs
@@ -3,30 +3,33 @@ use mozprofile::preferences::Pref;
 // ALL CHANGES TO THIS FILE MUST HAVE REVIEW FROM A GECKODRIVER PEER!
 //
 // The Marionette Python client is used out-of-tree with release
 // channel builds of Firefox.  Removing a preference from this file
 // will cause regressions, so please be careful and get review from
 // a Testing :: Marionette peer before you make any changes to this file.
 
 lazy_static! {
-    pub static ref DEFAULT: [(&'static str, Pref); 52] = [
+    pub static ref DEFAULT: [(&'static str, Pref); 53] = [
         // Make sure Shield doesn't hit the network.
         ("app.normandy.api_url", Pref::new("")),
 
         // Disable automatic downloading of new releases
         ("app.update.auto", Pref::new(false)),
 
         // Disable automatically upgrading Firefox
         ("app.update.enabled", Pref::new(false)),
 
         // Enable the dump function, which sends messages to the system
         // console
         ("browser.dom.window.dump.enabled", Pref::new(true)),
 
+        // Disable Photon onboarding experience
+        ("browser.onboarding.enabled", Pref::new(false)),
+
         // Disable safebrowsing components
         ("browser.safebrowsing.blockedURIs.enabled", Pref::new(false)),
         ("browser.safebrowsing.downloads.enabled", Pref::new(false)),
         ("browser.safebrowsing.passwords.enabled", Pref::new(false)),
         ("browser.safebrowsing.malware.enabled", Pref::new(false)),
         ("browser.safebrowsing.phishing.enabled", Pref::new(false)),
 
         // Do not restore the last open set of tabs if the browser crashed

--- a/testing/marionette/client/marionette_driver/geckoinstance.py
+++ b/testing/marionette/client/marionette_driver/geckoinstance.py
@@ -509,16 +509,19 @@ class DesktopInstance(GeckoInstance):
 
         # Indicate that the download panel has been shown once so that whichever
         # download test runs first doesn"t show the popup inconsistently
         "browser.download.panel.shown": True,
 
         # Do not show the EULA notification which can interfer with tests
         "browser.EULA.override": True,
 
+        # Disable Photon onboarding experience
+        "broswer.onboarding.enabled": False,
+
         # Background thumbnails in particular cause grief, and disabling thumbnails
         # in general can"t hurt - we re-enable them when tests need them
         "browser.pagethumbnails.capturing_disabled": True,
 
         # Disable safebrowsing components
         "browser.safebrowsing.blockedURIs.enabled": False,
         "browser.safebrowsing.downloads.enabled": False,
         "browser.safebrowsing.passwords.enabled": False,

--- a/testing/marionette/components/marionette.js
+++ b/testing/marionette/components/marionette.js
@@ -75,16 +75,19 @@ const RECOMMENDED_PREFS = new Map([
   // (bug 1176798, bug 1177018, bug 1210465)
   ["apz.content_response_timeout", 60000],
 
   // Indicate that the download panel has been shown once so that
   // whichever download test runs first doesn't show the popup
   // inconsistently.
   ["browser.download.panel.shown", true],
 
+  // Disable Photon onboarding experience
+  ["browser.onboarding.enabled", false],
+
   // Background thumbnails in particular cause grief, and disabling
   // thumbnails in general cannot hurt
   ["browser.pagethumbnails.capturing_disabled", true],
 
   // Disable safebrowsing components.
   //
   // These should also be set in the profile prior to starting Firefox,
   // as it is picked up at runtime.