Fixing the fix...

dist/preview release/babylon.max.js

@@ -67242,7 +67242,7 @@ var BABYLON;
             } };
             engine.onVRRequestPresentComplete.add(_this._onVREnabled);
             engine.initWebVR().add(function (event) {
-                if (!_this._vrDevice || _this._vrDevice === event.vrDisplay) {
+                if (!event.vrDisplay || _this._vrDevice === event.vrDisplay) {
                     return;
                 }
                 _this._vrDevice = event.vrDisplay;

dist/preview release/customConfigurations/minimalGLTFViewer/babylon.max.js

@@ -67242,7 +67242,7 @@ var BABYLON;
             } };
             engine.onVRRequestPresentComplete.add(_this._onVREnabled);
             engine.initWebVR().add(function (event) {
-                if (!_this._vrDevice || _this._vrDevice === event.vrDisplay) {
+                if (!event.vrDisplay || _this._vrDevice === event.vrDisplay) {
                     return;
                 }
                 _this._vrDevice = event.vrDisplay;

src/Cameras/VR/babylon.webVRCamera.ts

@@ -99,7 +99,7 @@ module BABYLON {
             this._onVREnabled = (success: boolean) => { if (success) { this.initControllers(); } };
             engine.onVRRequestPresentComplete.add(this._onVREnabled);
             engine.initWebVR().add((event: IDisplayChangedEventArgs) => {
-                if (!this._vrDevice || this._vrDevice === event.vrDisplay) {
+                if (!event.vrDisplay || this._vrDevice === event.vrDisplay) {
                     return;
                 }