messaging.onBackgroundMessage does not prevent the default notification

[Qendolin]

The comment here says onBackgroundMessage can be used to customize background messages which is true by itself but the problem is that the default notification is still shown by the Firebase SDK. This seems to be an issue with the SDK itself since there is currently no way to prevent the default notification , however I think this issue should also be noted in the comment.

Here is the relevant code from the onPush method

// background handling: display and pass to onBackgroundMessage hook
let isNotificationShown = false;
if (!!internalPayload.notification) {
  await showNotification(wrapInternalPayload(internalPayload));
  isNotificationShown = true;
}

// MessagePayload is only passed to `onBackgroundMessage`. Skip passing MessagePayload for
// the legacy `setBackgroundMessageHandler` to preserve the SDK behaviors.
if (
  isNotificationShown === true &&
  this.isOnBackgroundMessageUsed === false
) {
  return;
}

if (!!this.bgMessageHandler) {
  const payload = externalizePayload(internalPayload);

  if (typeof this.bgMessageHandler === 'function') {
    this.bgMessageHandler(payload);
  } else {
    this.bgMessageHandler.next(payload);
  }
}

The only case where showNotification is not called is when internalPayload.notification is falsy.

[hashtag32]

I agree. With the provided code here, it shows a double notification every time. One is customized and one seems to be a default message.
Both messages disappear when the L55 is commented.
Why is nobody else encountering this error?

[Suketu-Patel]

I found a workaround for this issue.
#410 (comment)

[miloskroulik]

I've encountered this issue as well.

[sudosu]

Same annoying issue!