Skip idle when transient connection

app/src/main/java/eu/faircode/email/ServiceSynchronize.java

@@ -1283,6 +1283,7 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                             });
 
                             // Idle folder
+                            if (!account.isTransient(this)) {
                                 Thread idler = new Thread(new Runnable() {
                                     @Override
                                     public void run() {
@@ -1307,6 +1308,7 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                                 idler.setPriority(THREAD_PRIORITY_BACKGROUND);
                                 idler.start();
                                 idlers.add(idler);
+                            }
 
                             EntityOperation.sync(this, folder.id, false, force && !forced);