diff --git a/app/build.gradle b/app/build.gradle
index 20ef60b9..450b7521 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -31,8 +31,8 @@ android {
         testApplicationId "ac.mdiq.podcini.tests"
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
 
-        versionCode 3020234
-        versionName "6.5.0.1"
+        versionCode 3020235
+        versionName "6.5.1"
 
         applicationId "ac.mdiq.podcini.R"
         def commit = ""
diff --git a/app/proguard.cfg b/app/proguard.cfg
index 4b22dc08..25717d63 100644
--- a/app/proguard.cfg
+++ b/app/proguard.cfg
@@ -71,4 +71,3 @@
 -dontwarn java.lang.management.ThreadMXBean
 
 -dontwarn org.slf4j.impl.StaticLoggerBinder
-# -dontwarn java.beans.BeanDescriptor
diff --git a/app/src/main/kotlin/ac/mdiq/podcini/ui/activity/VideoplayerActivity.kt b/app/src/main/kotlin/ac/mdiq/podcini/ui/activity/VideoplayerActivity.kt
index 84e493e0..3153486c 100644
--- a/app/src/main/kotlin/ac/mdiq/podcini/ui/activity/VideoplayerActivity.kt
+++ b/app/src/main/kotlin/ac/mdiq/podcini/ui/activity/VideoplayerActivity.kt
@@ -104,6 +104,7 @@ class VideoplayerActivity : CastEnabledActivity() {
     private fun setForVideoMode() {
         when (videoMode) {
             VideoMode.FULL_SCREEN_VIEW -> {
+                window.clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN)
                 window.addFlags(WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN)
                 setTheme(R.style.Theme_Podcini_VideoPlayer)
                 requestedOrientation = ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE
@@ -111,13 +112,16 @@ class VideoplayerActivity : CastEnabledActivity() {
                 window.setFormat(PixelFormat.TRANSPARENT)
             }
             VideoMode.WINDOW_VIEW -> {
+                window.clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN)
+                window.clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN)
                 setTheme(R.style.Theme_Podcini_VideoEpisode)
-                requestedOrientation = ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED
+                requestedOrientation = ActivityInfo.SCREEN_ORIENTATION_PORTRAIT
                 window.setFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN, WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN)
                 window.setFormat(PixelFormat.TRANSPARENT)
             }
             else -> {}
         }
+        if (::videoEpisodeFragment.isInitialized) videoEpisodeFragment.setForVideoMode()
     }
 
     @UnstableApi
@@ -143,7 +147,6 @@ class VideoplayerActivity : CastEnabledActivity() {
         super.onDestroy()
     }
 
-
     public override fun onUserLeaveHint() {
         if (!PictureInPictureUtil.isInPictureInPictureMode(this)) compatEnterPictureInPicture()
     }
@@ -185,7 +188,7 @@ class VideoplayerActivity : CastEnabledActivity() {
         }
     }
 
-    fun onEventMainThread(event: FlowEvent.MessageEvent) {
+    private fun onEventMainThread(event: FlowEvent.MessageEvent) {
 //        Logd(TAG, "onEvent($event)")
         val errorDialog = MaterialAlertDialogBuilder(this)
         errorDialog.setMessage(event.message)
@@ -249,20 +252,20 @@ class VideoplayerActivity : CastEnabledActivity() {
 
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
         // some options option requires FeedItem
-        when {
-            item.itemId == R.id.player_switch_to_audio_only -> {
+        when (item.itemId) {
+            R.id.player_switch_to_audio_only -> {
                 switchToAudioOnly = true
                 finish()
                 return true
             }
-            item.itemId == android.R.id.home -> {
+            android.R.id.home -> {
                 val intent = Intent(this@VideoplayerActivity, MainActivity::class.java)
                 intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP or Intent.FLAG_ACTIVITY_NEW_TASK)
                 startActivity(intent)
                 finish()
                 return true
             }
-            item.itemId == R.id.player_show_chapters -> {
+            R.id.player_show_chapters -> {
                 ChaptersFragment().show(supportFragmentManager, ChaptersFragment.TAG)
                 return true
             }
diff --git a/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/AddFeedFragment.kt b/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/AddFeedFragment.kt
index 810499a6..65899532 100644
--- a/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/AddFeedFragment.kt
+++ b/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/AddFeedFragment.kt
@@ -171,7 +171,6 @@ class AddFeedFragment : Fragment() {
 
     @UnstableApi private fun addLocalFolderResult(uri: Uri?) {
         if (uri == null) return
-
         val scope = CoroutineScope(Dispatchers.Main)
         scope.launch {
             try {
diff --git a/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/AudioPlayerFragment.kt b/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/AudioPlayerFragment.kt
index 184f2f9c..4d528d73 100644
--- a/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/AudioPlayerFragment.kt
+++ b/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/AudioPlayerFragment.kt
@@ -555,7 +555,7 @@ class AudioPlayerFragment : Fragment(), SeekBar.OnSeekBarChangeListener, Toolbar
                         ensureService()
                         (activity as MainActivity).bottomSheet.setState(BottomSheetBehavior.STATE_EXPANDED)
                     } else {
-                        playPause()
+//                        playPause()
 //                        controller!!.ensureService()
                         val intent = getPlayerActivityIntent(requireContext(), mediaType)
                         startActivity(intent)
diff --git a/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/OnlineFeedViewFragment.kt b/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/OnlineFeedViewFragment.kt
index ebcac640..2b17685a 100644
--- a/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/OnlineFeedViewFragment.kt
+++ b/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/OnlineFeedViewFragment.kt
@@ -218,7 +218,6 @@ class OnlineFeedViewFragment : Fragment() {
                     break
                 }
             }
-
             if (url != null) {
                 Logd(TAG, "Successfully retrieve feed url")
                 isFeedFoundBySearch = true
@@ -268,9 +267,9 @@ class OnlineFeedViewFragment : Fragment() {
                     try {
                         val channelTabInfo = ChannelTabInfo.getInfo(service, channelInfo.tabs.first())
                         Logd(TAG, "startFeedBuilding result1: $channelTabInfo ${channelTabInfo.relatedItems.size}")
+                        selectedDownloadUrl = prepareUrl(url)
                         val feed_ = Feed(selectedDownloadUrl, null)
                         feed_.id = 1234567889L
-                        selectedDownloadUrl = prepareUrl(url)
                         feed_.type = Feed.FeedType.YOUTUBE.name
                         feed_.hasVideoMedia = true
                         feed_.title = channelInfo.name
@@ -479,6 +478,7 @@ class OnlineFeedViewFragment : Fragment() {
                         }
                         val fo = updateFeed(requireContext(), feed, false)
                         Logd(TAG, "fo.id: ${fo?.id} feed.id: ${feed.id}")
+//                        feeds = getFeedList()
                     }
                     withContext(Dispatchers.Main) {
                         didPressSubscribe = true
@@ -521,8 +521,6 @@ class OnlineFeedViewFragment : Fragment() {
     }
 
     @UnstableApi private fun openFeed() {
-        // feed.getId() is always 0, we have to retrieve the id from the feed list from
-        // the database
         (activity as MainActivity).loadFeedFragmentById(feedId, null)
     }
 
@@ -542,6 +540,9 @@ class OnlineFeedViewFragment : Fragment() {
         if (dli == null || selectedDownloadUrl == null) return
 
         when {
+//            feedSource != "VistaGuide" -> {
+//                binding.subscribeButton.isEnabled = false
+//            }
             dli.isDownloadingEpisode(selectedDownloadUrl!!) -> {
                 binding.subscribeButton.isEnabled = false
                 binding.subscribeButton.setText(R.string.subscribing_label)
@@ -695,7 +696,6 @@ class OnlineFeedViewFragment : Fragment() {
         fun findLinks(inVal: File, baseUrl: String): Map<String, String> {
             return findLinks(Jsoup.parse(inVal), baseUrl)
         }
-
         /**
          * Discovers links to RSS and Atom feeds in the given File which must be a HTML document.
          * @return A map which contains the feed URLs as keys and titles as values (the feed URL is also used as a title if
diff --git a/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/VideoEpisodeFragment.kt b/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/VideoEpisodeFragment.kt
index 1346aa6e..944f3adf 100644
--- a/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/VideoEpisodeFragment.kt
+++ b/app/src/main/kotlin/ac/mdiq/podcini/ui/fragment/VideoEpisodeFragment.kt
@@ -30,6 +30,7 @@ import ac.mdiq.podcini.ui.view.ShownotesWebView
 import ac.mdiq.podcini.storage.utils.DurationConverter.getDurationStringLong
 import ac.mdiq.podcini.util.Logd
 import ac.mdiq.podcini.storage.utils.TimeSpeedConverter
+import ac.mdiq.podcini.ui.activity.VideoplayerActivity.VideoMode
 import ac.mdiq.podcini.util.EventFlow
 import ac.mdiq.podcini.util.FlowEvent
 import android.os.Bundle
@@ -74,7 +75,7 @@ class VideoEpisodeFragment : Fragment(), OnSeekBarChangeListener {
     private var itemsLoaded = false
     private var episode: Episode? = null
     private var webviewData: String? = null
-    private lateinit var webvDescription: ShownotesWebView
+    var webvDescription: ShownotesWebView? = null
 
     var destroyingDueToReload = false
     var controller: ServiceStatusHandler? = null
@@ -123,8 +124,10 @@ class VideoEpisodeFragment : Fragment(), OnSeekBarChangeListener {
         override fun surfaceDestroyed(holder: SurfaceHolder) {
             Logd(TAG, "Videosurface was destroyed")
             videoSurfaceCreated = false
-            if (controller != null && !destroyingDueToReload && !(activity as VideoplayerActivity).switchToAudioOnly)
-                notifyVideoSurfaceAbandoned()
+            (activity as? VideoplayerActivity)?.finish()
+//            TODO: test
+//            if (controller != null && !destroyingDueToReload && !(activity as VideoplayerActivity).switchToAudioOnly)
+//                notifyVideoSurfaceAbandoned()
         }
     }
 
@@ -200,8 +203,10 @@ class VideoEpisodeFragment : Fragment(), OnSeekBarChangeListener {
 
     override fun onDestroyView() {
         Logd(TAG, "onDestroyView")
-        root.removeView(webvDescription)
-        webvDescription.destroy()
+        if (webvDescription != null) {
+            root.removeView(webvDescription!!)
+            webvDescription!!.destroy()
+        }
         _binding = null
         controller?.release()
         controller = null // prevent leak
@@ -227,6 +232,24 @@ class VideoEpisodeFragment : Fragment(), OnSeekBarChangeListener {
         }
     }
 
+    fun setForVideoMode() {
+        when (videoMode) {
+            VideoMode.FULL_SCREEN_VIEW ->{
+                webvDescription?.visibility = View.GONE
+                val layoutParams = binding.videoPlayerContainer.layoutParams
+                layoutParams.height = ViewGroup.LayoutParams.MATCH_PARENT
+                binding.videoPlayerContainer.layoutParams = layoutParams
+            }
+            VideoMode.WINDOW_VIEW -> {
+                webvDescription?.visibility = View.VISIBLE
+                val layoutParams = binding.videoPlayerContainer.layoutParams
+                layoutParams.height = ViewGroup.LayoutParams.WRAP_CONTENT
+                binding.videoPlayerContainer.layoutParams = layoutParams
+            }
+            else -> {}
+        }
+    }
+
     private fun bufferUpdate(event: FlowEvent.BufferUpdateEvent) {
         when {
             event.hasStarted() -> binding.progressBar.visibility = View.VISIBLE
@@ -289,7 +312,7 @@ class VideoEpisodeFragment : Fragment(), OnSeekBarChangeListener {
                                 invalidateOptionsMenu(requireActivity())
                             }
                         }
-                        if (webviewData != null && !itemsLoaded) webvDescription.loadDataWithBaseURL("https://127.0.0.1", webviewData!!,
+                        if (webviewData != null && !itemsLoaded) webvDescription?.loadDataWithBaseURL("https://127.0.0.1", webviewData!!,
                             "text/html", "utf-8", "about:blank")
 
                         itemsLoaded = true
@@ -375,7 +398,9 @@ class VideoEpisodeFragment : Fragment(), OnSeekBarChangeListener {
     fun toggleVideoControlsVisibility() {
         if (videoControlsShowing) {
             hideVideoControls(true)
-            if (videoMode == VideoplayerActivity.VideoMode.FULL_SCREEN_VIEW) (activity as AppCompatActivity).supportActionBar?.hide()
+            if (videoMode == VideoplayerActivity.VideoMode.FULL_SCREEN_VIEW) {
+                (activity as AppCompatActivity).supportActionBar?.hide()
+            }
         } else {
             showVideoControls()
             (activity as AppCompatActivity).supportActionBar?.show()
@@ -456,7 +481,7 @@ class VideoEpisodeFragment : Fragment(), OnSeekBarChangeListener {
         }
         (activity as AppCompatActivity).window.decorView.systemUiVisibility = (View.SYSTEM_UI_FLAG_LAYOUT_STABLE or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN)
 //        binding.videoView.systemUiVisibility = View.SYSTEM_UI_FLAG_VISIBLE
-        binding.bottomControlsContainer.fitsSystemWindows = true
+//        binding.bottomControlsContainer.fitsSystemWindows = true
     }
 
     fun hideVideoControls(showAnimation: Boolean) {
@@ -472,7 +497,7 @@ class VideoEpisodeFragment : Fragment(), OnSeekBarChangeListener {
 //        (activity as AppCompatActivity).window.decorView.systemUiVisibility = (View.SYSTEM_UI_FLAG_LOW_PROFILE
 //                or View.SYSTEM_UI_FLAG_FULLSCREEN or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
 //                or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION)
-        binding.bottomControlsContainer.fitsSystemWindows = true
+//        binding.bottomControlsContainer.fitsSystemWindows = true
         binding.bottomControlsContainer.visibility = View.GONE
         binding.controlsContainer.visibility = View.GONE
     }
diff --git a/app/src/main/res/layout/video_episode_fragment.xml b/app/src/main/res/layout/video_episode_fragment.xml
index 1039ef0d..2d0943b2 100644
--- a/app/src/main/res/layout/video_episode_fragment.xml
+++ b/app/src/main/res/layout/video_episode_fragment.xml
@@ -8,15 +8,15 @@
                 android:id="@+id/videoEpisodeContainer">
 
     <FrameLayout
+        android:id="@+id/videoPlayerContainer"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:background="@color/black"
-        android:id="@+id/videoPlayerContainer">
+        android:background="@color/black">
 
         <ac.mdiq.podcini.ui.view.AspectRatioVideoView
             android:id="@+id/videoView"
             android:layout_width="match_parent"
-            android:layout_height="wrap_content"
+            android:layout_height="match_parent"
             android:layout_gravity="center" />
 
         <ProgressBar
@@ -183,7 +183,6 @@
             </RelativeLayout>
 
         </LinearLayout>
-
     </FrameLayout>
 
     <ac.mdiq.podcini.ui.view.ShownotesWebView
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index b672b111..57057d0c 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -239,6 +239,8 @@
 
     <style name="Theme.Podcini.VideoPlayer" parent="@style/Theme.Podcini.Dark">
         <item name="windowActionBarOverlay">true</item>
+        <item name="windowActionBar">false</item>
+        <item name="windowNoTitle">true</item>
     </style>
 
     <style name="Podcini.TextView.Heading" parent="@android:style/TextAppearance.Medium">
diff --git a/changelog.md b/changelog.md
index 18fe16f4..ddbeb454 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,3 +1,8 @@
+# 6.5.1
+
+* further improved behavior in video player, seamless switch among audio-only, window and fullscreen modes, and automatical switch to audio when exit
+* fixed issue of OnlineFeed view not transition to FeedEpisodes view when subscribing a Youtube channel
+
 # 6.5.0.1
 
 * fixed release app being improperly stripped of classes by R8
diff --git a/fastlane/metadata/android/en-US/changelogs/3020234.txt b/fastlane/metadata/android/en-US/changelogs/3020234.txt
index 9f07dab2..5a4b840e 100644
--- a/fastlane/metadata/android/en-US/changelogs/3020234.txt
+++ b/fastlane/metadata/android/en-US/changelogs/3020234.txt
@@ -1,3 +1,3 @@
- Version 6.5.1 brings several changes:
+ Version 6.5.0.1 brings several changes:
 
 * fixed release app being improperly stripped of classes by R8
diff --git a/fastlane/metadata/android/en-US/changelogs/3020235.txt b/fastlane/metadata/android/en-US/changelogs/3020235.txt
new file mode 100644
index 00000000..7e3b0b60
--- /dev/null
+++ b/fastlane/metadata/android/en-US/changelogs/3020235.txt
@@ -0,0 +1,4 @@
+ Version 6.5.1 brings several changes:
+
+* further improved behavior in video player, seamless switch among audio-only, window and fullscreen modes, and automatical switch to audio when exit
+* fixed issue of OnlineFeed view not transition to FeedEpisodes view when subscribing a Youtube channel