2 files changed, 25 insertions, 1 deletions

diff --git a/ext/mixed/js/dom.js b/ext/mixed/js/dom.js
index 05764443..59fea9f6 100644
--- a/ext/mixed/js/dom.js
+++ b/ext/mixed/js/dom.js
@@ -77,6 +77,24 @@ class DOM {
         return (typeof key === 'string' ? (key.length === 1 ? key.toUpperCase() : key) : '');
     }
 
+    static addFullscreenChangeEventListener(onFullscreenChanged, eventListenerCollection=null) {
+        const target = document;
+        const options = false;
+        const fullscreenEventNames = [
+            'fullscreenchange',
+            'MSFullscreenChange',
+            'mozfullscreenchange',
+            'webkitfullscreenchange'
+        ];
+        for (const eventName of fullscreenEventNames) {
+            if (eventListenerCollection === null) {
+                target.addEventListener(eventName, onFullscreenChanged, options);
+            } else {
+                eventListenerCollection.addEventListener(target, eventName, onFullscreenChanged, options);
+            }
+        }
+    }
+
     static getFullscreenElement() {
         return (
             document.fullscreenElement ||
diff --git a/ext/mixed/js/text-scanner.js b/ext/mixed/js/text-scanner.js
index fb275452..7c705fc8 100644
--- a/ext/mixed/js/text-scanner.js
+++ b/ext/mixed/js/text-scanner.js
@@ -28,6 +28,7 @@ class TextScanner extends EventDispatcher {
         this._ignorePoint = ignorePoint;
         this._search = search;
 
+        this._isPrepared = false;
         this._ignoreNodes = null;
 
         this._causeCurrent = null;
@@ -69,10 +70,15 @@ class TextScanner extends EventDispatcher {
         return this._causeCurrent;
     }
 
+    prepare() {
+        this._isPrepared = true;
+        this.setEnabled(this._enabled);
+    }
+
     setEnabled(enabled) {
         this._eventListeners.removeAllEventListeners();
         this._enabled = enabled;
-        if (this._enabled) {
+        if (this._enabled && this._isPrepared) {
             this._hookEvents();
         } else {
             this.clearSelection(true);