title: White screen when closing Android keyboard
body: <p>I'm creating an hybrid application with WebView system and I have an issue with Android : when I tap on an input, the keyboard shows up, I write what I want and when the keyboard disappear, he leaves a white background that makes its size.</p>
  
  <p>Here is a screeshot of the problem. First screen is when the keyboard is open and the second one is when the keyboard is closed.</p>
  
  <p><a href="https://i.stack.imgur.com/4ZKGT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/4ZKGT.png" alt="Keyboard opening"></a>
  <a href="https://i.stack.imgur.com/F3oHP.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/F3oHP.png" alt="After closing the keyboard"></a></p>
  
  <p>I did a lot of research and still haven't found a good solution...
  I already haved seen <a href="https://stackoverflow.com/questions/35201412/android-white-background-when-keyboard-fades-away">this topic</a> but it doesn't work for me.</p>
  
  <p>Here is my MainActivity : </p>
  
  <pre><code>[Activity(
      Icon = "@drawable/icon",
      Theme = "@style/MyTheme",
      LaunchMode = Android.Content.PM.LaunchMode.SingleTop,
      ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation,
      WindowSoftInputMode = SoftInput.AdjustPan, 
      HardwareAccelerated = true
  )]
  public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity
  {
  </code></pre>
  
  <p>And here my androidManifest : </p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
   &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android" package="fr.beautiful.app" 
      android:installLocation="auto" android:versionName="1.0" android:versionCode="1" 
      android:windowSoftInputMode="adjustPan"&gt;
  &lt;uses-sdk android:minSdkVersion="15" android:targetSdkVersion="28" /&gt;
  &lt;uses-permission android:name="android.permission.INTERNET" /&gt;
  &lt;uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /&gt;
  &lt;uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" /&gt;
  &lt;uses-permission android:name="android.permission.WAKE_LOCK" /&gt;
  &lt;uses-permission android:name="fr.edition.ftel.cosoft.permission.C2D_MESSAGE" /&gt;
  &lt;uses-permission android:name="android.permission.READ_PHONE_STATE" /&gt;
  &lt;uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /&gt;
  &lt;uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /&gt;
    &lt;application android:label="BeautifulApp" android:icon="@drawable/icon"&gt;
      &lt;receiver android:name="com.google.firebase.iid.FirebaseInstanceIdInternalReceiver" 
        android:exported="false" /&gt;
      &lt;receiver android:name="com.google.firebase.iid.FirebaseInstanceIdReceiver" 
        android:exported="true" android:permission="com.google.android.c2dm.permission.SEND"&gt;
          &lt;intent-filter&gt;
              &lt;action android:name="com.google.android.c2dm.intent.RECEIVE" /&gt;
              &lt;action android:name="com.google.android.c2dm.intent.REGISTRATION" /&gt;
              &lt;category android:name="${applicationId}" /&gt;
          &lt;/intent-filter&gt;
      &lt;/receiver&gt;
    &lt;/application&gt;
  &lt;/manifest&gt;
  </code></pre>
  
  <p>I’ve tried almost every windowSoftInputMode but none seem to work.
  Finally, the bug does not occur on all devices but only the most recent</p>
  
  <p>Do you have any idea to help me ? 
  Thanks in advance.</p>