--- a/browser/modules/test/browser_BrowserUITelemetry_defaults.js
+++ b/browser/modules/test/browser_BrowserUITelemetry_defaults.js
@@ -5,22 +5,28 @@
 
 function test() {
   let s = {};
   Cu.import("resource:///modules/CustomizableUI.jsm", s);
   Cu.import("resource:///modules/BrowserUITelemetry.jsm", s);
 
   let { CustomizableUI, BrowserUITelemetry } = s;
 
-  Assert.ok(CustomizableUI.inDefaultState,
-            "No other test should have left CUI in a dirty state.");
+  // Bug 1278176 - DevEdition never has the UI in a default state by default.
+  if (!AppConstants.MOZ_DEV_EDITION) {
+    Assert.ok(CustomizableUI.inDefaultState,
+              "No other test should have left CUI in a dirty state.");
+  }
 
   let result = BrowserUITelemetry._getWindowMeasurements(window, 0);
 
-  Assert.deepEqual(result.defaultMoved, []);
+  // Bug 1278176 - DevEdition always reports the developer-button is moved.
+  if (!AppConstants.MOZ_DEV_EDITION) {
+    Assert.deepEqual(result.defaultMoved, []);
+  }
   Assert.deepEqual(result.nondefaultAdded, []);
   // This one is a bit weird - the "social-share-button" is dynamically added
   // to the toolbar as the feature is first used - but it's listed as being in
   // the toolbar by default so it doesn't end up in nondefaultAdded once it
   // is created. The end result is that it ends up in defaultRemoved before
   // the feature has been activated.
   // Bug 1273358 exists to fix this.
   Assert.deepEqual(result.defaultRemoved, ["social-share-button"]);