perf: extension onStart hook will block task create (#844)

pkg/download/downloader.go

@@ -1018,8 +1018,6 @@ func (d *Downloader) doStart(task *Task) (err error) {
 			return
 		}
 		isCreate = task.Status == base.DownloadStatusReady
-
-		d.triggerOnStart(task)
 		task.updateStatus(base.DownloadStatusRunning)
 
 		return
@@ -1036,6 +1034,7 @@ func (d *Downloader) doStart(task *Task) (err error) {
 		task.lock.Lock()
 		defer task.lock.Unlock()
 
+		d.triggerOnStart(task)
 		if task.Meta.Res == nil {
 			err := task.fetcher.Resolve(task.Meta.Req)
 			if err != nil {

ui/flutter/lib/util/message.dart

@@ -8,9 +8,16 @@ void showErrorMessage(msg) {
     Get.snackbar(title, msg.msg!);
     return;
   }
-  if (msg is Exception && (msg as dynamic).message is Result) {
-    Get.snackbar(title, ((msg as dynamic).message as Result).msg!);
-    return;
+  if (msg is Exception) {
+    final message = (msg as dynamic).message;
+    if (message is Result) {
+      Get.snackbar(title, ((msg as dynamic).message as Result).msg!);
+      return;
+    }
+    if (message is String) {
+      Get.snackbar(title, message);
+      return;
+    }
   }
   Get.snackbar(title, msg.toString());
 }