-Added back button press check to destroy rather than minimize main video player.

app/src/main/java/org/schabi/newpipe/player/MainVideoPlayer.java

@@ -104,6 +104,7 @@ public final class MainVideoPlayer extends AppCompatActivity
 
     @Nullable private PlayerState playerState;
     private boolean isInMultiWindow;
+    private boolean isBackPressed;
 
     /*//////////////////////////////////////////////////////////////////////////
     // Activity LifeCycle
@@ -191,6 +192,12 @@ public final class MainVideoPlayer extends AppCompatActivity
         }
     }
 
+    @Override
+    public void onBackPressed() {
+        super.onBackPressed();
+        isBackPressed = true;
+    }
+
     @Override
     protected void onSaveInstanceState(Bundle outState) {
         if (DEBUG) Log.d(TAG, "onSaveInstanceState() called");
@@ -211,9 +218,15 @@ public final class MainVideoPlayer extends AppCompatActivity
         PlayerHelper.setScreenBrightness(getApplicationContext(),
                 getWindow().getAttributes().screenBrightness);
 
-        isInMultiWindow = false;
+        if (playerImpl == null) return;
+        if (isBackPressed) {
+            playerImpl.destroy();
+        } else {
+            playerImpl.minimize();
+        }
 
-        if (playerImpl != null) playerImpl.terminate();
+        isInMultiWindow = false;
+        isBackPressed = false;
     }
 
     /*//////////////////////////////////////////////////////////////////////////
@@ -443,7 +456,7 @@ public final class MainVideoPlayer extends AppCompatActivity
             switchPopupButton.setOnClickListener(this);
         }
 
-        public void terminate() {
+        public void minimize() {
             switch (PlayerHelper.getMinimizeOnExitAction(context)) {
                 case PlayerHelper.MinimizeMode.MINIMIZE_ON_EXIT_MODE_BACKGROUND:
                     onPlayBackgroundButtonClicked();

app/src/main/res/values/strings.xml

@@ -505,8 +505,8 @@
     </string-array>
 
     <!-- Minimize to exit action -->
-    <string name="minimize_on_exit_title">Minimize on exit</string>
-    <string name="minimize_on_exit_summary">Action when exiting main video player — %s</string>
+    <string name="minimize_on_exit_title">Minimize on application switch</string>
+    <string name="minimize_on_exit_summary">Action when switching to other application from main video player — %s</string>
     <string name="minimize_on_exit_none_description">None</string>
     <string name="minimize_on_exit_background_description">Minimize to background player</string>
     <string name="minimize_on_exit_popup_description">Minimize to popup player</string>