diff --git a/.babelrc.js b/.babelrc.js
index 2ddd5a3..1a1aa4b 100644
--- a/.babelrc.js
+++ b/.babelrc.js
@@ -1,5 +1,15 @@
 module.exports = {
-  presets: ['@babel/preset-env', '@babel/preset-react'],
+  presets: [
+    [
+      '@babel/preset-env',
+      {
+        targets: {
+          node: 'current',
+        },
+      },
+    ],
+    '@babel/preset-react'
+  ],
   plugins: [
     // Preact
     ['@babel/plugin-transform-react-jsx', { pragma: 'h' }],
diff --git a/jsconfig.json b/jsconfig.json
new file mode 100644
index 0000000..93193ca
--- /dev/null
+++ b/jsconfig.json
@@ -0,0 +1,11 @@
+{
+  "compilerOptions": {
+    "resolveJsonModule": true,
+    "baseUrl": ".",
+    "paths": {
+      "@common": ["./src/common"],
+      "@common/*": ["./src/common/*"],
+    }
+  },
+  "exclude": ["node_modules", "build"]
+}
diff --git a/package-lock.json b/package-lock.json
index b8ed5df..f67d044 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "prismic-toolbar",
-  "version": "4.0.2",
+  "version": "4.0.5",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
diff --git a/package.json b/package.json
index a8c5b08..cf44afa 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "prismic-toolbar",
-  "version": "4.0.4",
+  "version": "4.0.6",
   "description": "Prismic Toolbar",
   "license": "Apache-2.0",
   "main": "build/prismic-toolbar.js",
diff --git a/src/common/events.js b/src/common/events.js
new file mode 100644
index 0000000..e222fc6
--- /dev/null
+++ b/src/common/events.js
@@ -0,0 +1,20 @@
+export const toolbarEvents = {
+  prismic: 'prismic',
+  previewUpdate: 'prismicPreviewUpdate',
+  previewEnd: 'prismicPreviewEnd'
+};
+
+/**
+ * Dispatches an event with given data
+ *
+ * @param {string} event - Event name
+ * @param {?any} data - Data to attach to the event
+ *
+ * @return {boolean} - `true` if event `event.preventDefault()`
+ * was not called (event was not cancelled)
+ */
+export const dispatchToolbarEvent = (event, data = null) =>
+  window.dispatchEvent(new CustomEvent(event, {
+    detail: data,
+    cancelable: true
+  }));
diff --git a/src/common/index.js b/src/common/index.js
index 7bb54f5..343cf94 100644
--- a/src/common/index.js
+++ b/src/common/index.js
@@ -2,6 +2,10 @@
 export { getCookie, setCookie, deleteCookie, demolishCookie } from './cookie';
 export { Hooks } from './hooks';
 export { Sorter } from './sorter';
+export {
+  toolbarEvents,
+  dispatchToolbarEvent,
+} from './events';
 export {
   warn,
   err,
diff --git a/src/iframe/preview.js b/src/iframe/preview.js
index 46842f8..19d568e 100644
--- a/src/iframe/preview.js
+++ b/src/iframe/preview.js
@@ -1,4 +1,4 @@
-import { fetchy, query, getCookie, demolishCookie, throttle, memoize, once } from '@common';
+import { fetchy, query, getCookie, demolishCookie, throttle, memoize } from '@common';
 
 const SESSION_ID = getCookie('io.prismic.previewSession');
 
@@ -11,7 +11,14 @@ const PreviewRef = {
   getCurrent: throttle(async () => {
     const s = await State.get();
     const ref = encodeURIComponent(s.preview.ref);
-    return fetchy({ url: `/previews/${SESSION_ID}/ping?ref=${ref}` });
+    const current = await fetchy({ url: `/previews/${SESSION_ID}/ping?ref=${ref}` });
+
+    if (typeof s.preview === 'object') {
+      s.preview.ref = current.ref;
+      State.set(s);
+    }
+
+    return current;
   }, 2000)
 };
 
@@ -65,12 +72,30 @@ const Share = {
 const State = {
   liveStateNeeded: Boolean(getCookie('is-logged-in')) || Boolean(getCookie('io.prismic.previewSession')),
 
-  get: once(async () => {
-    if (!State.liveStateNeeded) return State.normalize();
-    return fetchy({
-      url: '/toolbar/state',
-    }).then(State.normalize);
-  }),
+  state: null,
+
+  get: async () => {
+    if (!State.state) {
+      await State.insert();
+    }
+    return State.state;
+  },
+
+  set: (newState = {}) => {
+    State.state = newState;
+  },
+
+  setNormalized: (newState = {}) => {
+    State.set(State.normalize(newState));
+  },
+
+  insert: async () => {
+    if (!State.liveStateNeeded) {
+      State.setNormalized();
+    } else {
+      State.setNormalized(await fetchy({ url: '/toolbar/state' }));
+    }
+  },
 
   normalize: (_state = {}) => (
     Object.assign({}, {
diff --git a/src/toolbar/index.js b/src/toolbar/index.js
index 23aab29..c697fbf 100644
--- a/src/toolbar/index.js
+++ b/src/toolbar/index.js
@@ -1,6 +1,6 @@
 import './checkBrowser';
 import { ToolbarService } from '@toolbar-service';
-import { script } from '@common';
+import { toolbarEvents, dispatchToolbarEvent, script } from '@common';
 import { reloadOrigin, getAbsoluteURL } from './utils';
 import { Preview } from './preview';
 import { Prediction } from './prediction';
@@ -40,7 +40,7 @@ window.prismic = window.PrismicToolbar = {
 let repos = new Set();
 
 // Prismic variable is available
-window.dispatchEvent(new CustomEvent('prismic'));
+dispatchToolbarEvent(toolbarEvents.prismic);
 
 // Auto-querystring setup
 const scriptURL = new URL(getAbsoluteURL(document.currentScript.getAttribute('src')));
@@ -56,10 +56,11 @@ if (legacyEndpoint) {
 
 if (!repos.size) warn`Your are not connected to a repository.`;
 
-repos.forEach(setup);
-
 // Setup the Prismic Toolbar for one repository TODO support multi-repo
 let setupDomain = null;
+
+repos.forEach(setup);
+
 async function setup (rawInput) {
   // Validate repository
   const domain = parseEndpoint(rawInput);
diff --git a/src/toolbar/preview/index.js b/src/toolbar/preview/index.js
index 6fc6b11..24e13e4 100644
--- a/src/toolbar/preview/index.js
+++ b/src/toolbar/preview/index.js
@@ -1,4 +1,4 @@
-import { getLocation } from '@common';
+import { toolbarEvents, dispatchToolbarEvent, getLocation } from '@common';
 import { reloadOrigin } from '../utils';
 import screenshot from './screenshot';
 
@@ -44,7 +44,12 @@ export class Preview {
   async updatePreview() {
     const { reload, ref } = await this.client.updatePreview();
     this.start(ref);
-    if (reload) { reloadOrigin(); }
+    if (reload) {
+      // Dispatch the update event and hard reload if not cancelled by handlers
+      if (dispatchToolbarEvent(toolbarEvents.previewUpdate, { ref })) {
+        reloadOrigin();
+      }
+    }
   }
 
   // Start preview
@@ -67,8 +72,11 @@ export class Preview {
     await this.client.closePreviewSession();
     if (!this.cookie.getRefForDomain()) return;
     this.cookie.deletePreviewForDomain();
-    // reload to get rid of preview data and display the live version
-    reloadOrigin();
+
+    // Dispatch the end event and hard reload if not cancelled by handlers
+    if (dispatchToolbarEvent(toolbarEvents.previewEnd)) {
+      reloadOrigin();
+    }
   }
 
   async share() {