message life-time added

src/ui/MainWindowInner.qml

@@ -601,6 +601,14 @@ Item {
                 font.family:    ScreenTools.demiboldFontFamily
                 wrapMode:       TextEdit.WordWrap
                 color:          qgcPal.alertText
+
+                onTextChanged: {
+                    if (lifetimeTimer.running) {
+                        lifetimeTimer.restart()
+                    } else {
+                        lifetimeTimer.start() // has no effect if timer is running, hence the if clause
+                    }
+                }
             }
         }
 
@@ -644,6 +652,17 @@ Item {
                 }
             }
         }
+
+        // Message life-time timer
+        Timer {
+            id: lifetimeTimer
+            interval: 10000 // ms
+            repeat: false
+
+            onTriggered: {
+                criticalMmessageArea.close()
+            }
+        }
     }
 
     //-------------------------------------------------------------------------