diff --git a/app/build.gradle b/app/build.gradle
index 6d2ad3726..4367e9856 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -135,7 +135,6 @@ dependencies {
     implementation 'com.google.android.material:material:1.2.1'
     implementation 'com.google.android:flexbox:1.1.0'
     implementation 'com.google.code.gson:gson:2.8.6'
-    testImplementation "androidx.room:room-testing:2.2.5"
 
     //lifecycle
     def lifecycle_version = '2.2.0'
diff --git a/app/src/main/java/io/legado/app/base/BaseActivity.kt b/app/src/main/java/io/legado/app/base/BaseActivity.kt
index 3ca496783..745813403 100644
--- a/app/src/main/java/io/legado/app/base/BaseActivity.kt
+++ b/app/src/main/java/io/legado/app/base/BaseActivity.kt
@@ -1,6 +1,7 @@
 package io.legado.app.base
 
 import android.content.Context
+import android.content.res.Configuration
 import android.os.Bundle
 import android.util.AttributeSet
 import android.view.Menu
@@ -15,6 +16,7 @@ import io.legado.app.constant.Theme
 import io.legado.app.lib.theme.ATH
 import io.legado.app.lib.theme.backgroundColor
 import io.legado.app.lib.theme.primaryColor
+import io.legado.app.ui.widget.TitleBar
 import io.legado.app.utils.*
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.MainScope
@@ -23,13 +25,22 @@ import kotlinx.coroutines.cancel
 
 abstract class BaseActivity(
     private val layoutID: Int,
-    private val fullScreen: Boolean = true,
+    val fullScreen: Boolean = true,
     private val theme: Theme = Theme.Auto,
     private val toolBarTheme: Theme = Theme.Auto,
     private val transparent: Boolean = false
 ) : AppCompatActivity(),
     CoroutineScope by MainScope() {
 
+    val isInMultiWindow: Boolean
+        get() {
+            return if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
+                isInMultiWindowMode
+            } else {
+                false
+            }
+        }
+
     override fun attachBaseContext(newBase: Context) {
         super.attachBaseContext(LanguageUtils.setConfiguration(newBase))
     }
@@ -52,10 +63,28 @@ abstract class BaseActivity(
         setupSystemBar()
         super.onCreate(savedInstanceState)
         setContentView(layoutID)
+        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
+            findViewById<TitleBar>(R.id.title_bar)
+                ?.onMultiWindowModeChanged(isInMultiWindowMode, fullScreen)
+        }
         onActivityCreated(savedInstanceState)
         observeLiveBus()
     }
 
+    override fun onMultiWindowModeChanged(isInMultiWindowMode: Boolean, newConfig: Configuration?) {
+        super.onMultiWindowModeChanged(isInMultiWindowMode, newConfig)
+        findViewById<TitleBar>(R.id.title_bar)
+            ?.onMultiWindowModeChanged(isInMultiWindowMode, fullScreen)
+        setupSystemBar()
+    }
+
+    override fun onConfigurationChanged(newConfig: Configuration) {
+        super.onConfigurationChanged(newConfig)
+        findViewById<TitleBar>(R.id.title_bar)
+            ?.onMultiWindowModeChanged(isInMultiWindow, fullScreen)
+        setupSystemBar()
+    }
+
     override fun onDestroy() {
         super.onDestroy()
         cancel()
@@ -120,7 +149,7 @@ abstract class BaseActivity(
     }
 
     private fun setupSystemBar() {
-        if (fullScreen) {
+        if (fullScreen && !isInMultiWindow) {
             window.clearFlags(
                 WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS
                         or WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION
diff --git a/app/src/main/java/io/legado/app/base/BaseFragment.kt b/app/src/main/java/io/legado/app/base/BaseFragment.kt
index c19033aa8..155bb6076 100644
--- a/app/src/main/java/io/legado/app/base/BaseFragment.kt
+++ b/app/src/main/java/io/legado/app/base/BaseFragment.kt
@@ -1,11 +1,14 @@
 package io.legado.app.base
 
 import android.annotation.SuppressLint
+import android.content.res.Configuration
 import android.os.Bundle
 import android.view.*
 import androidx.appcompat.view.SupportMenuInflater
 import androidx.appcompat.widget.Toolbar
 import androidx.fragment.app.Fragment
+import io.legado.app.R
+import io.legado.app.ui.widget.TitleBar
 import io.legado.app.utils.applyTint
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
@@ -36,12 +39,30 @@ abstract class BaseFragment(layoutID: Int) : Fragment(layoutID),
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
+        onMultiWindowModeChanged()
         onFragmentCreated(view, savedInstanceState)
         observeLiveBus()
     }
 
     abstract fun onFragmentCreated(view: View, savedInstanceState: Bundle?)
 
+    override fun onMultiWindowModeChanged(isInMultiWindowMode: Boolean) {
+        super.onMultiWindowModeChanged(isInMultiWindowMode)
+        onMultiWindowModeChanged()
+    }
+
+    override fun onConfigurationChanged(newConfig: Configuration) {
+        super.onConfigurationChanged(newConfig)
+        onMultiWindowModeChanged()
+    }
+
+    private fun onMultiWindowModeChanged() {
+        (activity as? BaseActivity)?.let {
+            view?.findViewById<TitleBar>(R.id.title_bar)
+                ?.onMultiWindowModeChanged(it.isInMultiWindow, it.fullScreen)
+        }
+    }
+
     override fun onDestroy() {
         super.onDestroy()
         job.cancel()
diff --git a/app/src/main/java/io/legado/app/data/entities/BookSource.kt b/app/src/main/java/io/legado/app/data/entities/BookSource.kt
index 9248a0a71..68a23b636 100644
--- a/app/src/main/java/io/legado/app/data/entities/BookSource.kt
+++ b/app/src/main/java/io/legado/app/data/entities/BookSource.kt
@@ -32,7 +32,7 @@ data class BookSource(
     var enabledExplore: Boolean = true,             // 启用发现
     var header: String? = null,                     // 请求头
     var loginUrl: String? = null,                   // 登录地址
-    var bookSourceComment: String? = "",            // 注释
+    var bookSourceComment: String? = null,            // 注释
     var lastUpdateTime: Long = 0,                   // 最后更新时间，用于排序
     var weight: Int = 0,                            // 智能排序的权重
     var exploreUrl: String? = null,                 // 发现url
@@ -161,6 +161,7 @@ data class BookSource(
                 && equal(bookSourceGroup, source.bookSourceGroup)
                 && bookSourceType == source.bookSourceType
                 && equal(bookUrlPattern, source.bookUrlPattern)
+                && equal(bookSourceComment, source.bookSourceComment)
                 && enabled == source.enabled
                 && enabledExplore == source.enabledExplore
                 && equal(header, source.header)
diff --git a/app/src/main/java/io/legado/app/ui/main/MainActivity.kt b/app/src/main/java/io/legado/app/ui/main/MainActivity.kt
index 7d6c71134..934bb56f8 100644
--- a/app/src/main/java/io/legado/app/ui/main/MainActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/main/MainActivity.kt
@@ -38,7 +38,7 @@ class MainActivity : VMBaseActivity<MainViewModel>(R.layout.activity_main),
     private var bookshelfReselected: Long = 0
     private var pagePosition = 0
     private val fragmentId = arrayOf(0, 1, 2, 3)
-    private val fragmentMap = mapOf<Int, Fragment>(
+    private val fragmentMap = mapOf(
         Pair(fragmentId[0], BookshelfFragment()),
         Pair(fragmentId[1], ExploreFragment()),
         Pair(fragmentId[2], RssFragment()),
diff --git a/app/src/main/java/io/legado/app/ui/widget/TitleBar.kt b/app/src/main/java/io/legado/app/ui/widget/TitleBar.kt
index 3b9d28757..39e1cd441 100644
--- a/app/src/main/java/io/legado/app/ui/widget/TitleBar.kt
+++ b/app/src/main/java/io/legado/app/ui/widget/TitleBar.kt
@@ -196,6 +196,10 @@ class TitleBar(context: Context, attrs: AttributeSet?) : AppBarLayout(context, a
         backgroundColor = Color.TRANSPARENT
     }
 
+    fun onMultiWindowModeChanged(isInMultiWindowMode: Boolean, fullScreen: Boolean) {
+        topPadding = if (!isInMultiWindowMode && fullScreen) context.statusBarHeight else 0
+    }
+
     private fun attachToActivity() {
         if (attachToActivity) {
             activity?.let {