Failed to construct 'Notification': Illegal constructor

I have lots of these errors. I think its a bug.

TypeError: Failed to construct 'Notification': Illegal constructor. Use ServiceWorkerRegistration.showNotification() instead.
    at https://test.talk.zabanshenas.com/assets/application-f90359a92de40a4e43d63e0189af9256e9f4eae2e14faf72e4f9ef70239f0943.js:12:14605
    at h (https://test.talk.zabanshenas.com/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:18:1869)
    at C (https://test.talk.zabanshenas.com/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:18:3255)
    at https://test.talk.zabanshenas.com/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:18:3745
    at e.invoke (https://test.talk.zabanshenas.com/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:11634)
    at e.flush (https://test.talk.zabanshenas.com/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:10577)
    at e.flush (https://test.talk.zabanshenas.com/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:12677)
    at e._end (https://test.talk.zabanshenas.com/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:17457)
    at MutationObserver._boundAutorunEnd (https://test.talk.zabanshenas.com/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:13591)

Did you figure this out? I’m getting lots of these too.

No. I tested the recent version, however, the problem still exists.

Can anyone suggest how I might go about figuring out what’s causing these errors? I have a lot of them in my logs. I don’t have any plugins apart from the official ones and my Discourse is up to date.

I’m also getting a lot of these ones and not sure if they’re related:

TypeError: Cannot read property 'get' of null
at toggleUserMenu (https://tfk.thefreekick.com/assets/application-33e7747c7d87dbd465e8f058373c19dd40307f27fac4d9dca97d7d2565a1f4a6.js:65:4916)
at https://tfk.thefreekick.com/assets/application-33e7747c7d87dbd465e8f058373c19dd40307f27fac4d9dca97d7d2565a1f4a6.js:68:3525
at t.value (https://tfk.thefreekick.com/assets/application-33e7747c7d87dbd465e8f058373c19dd40307f27fac4d9dca97d7d2565a1f4a6.js:68:3143)
at t.value (https://tfk.thefreekick.com/assets/application-33e7747c7d87dbd465e8f058373c19dd40307f27fac4d9dca97d7d2565a1f4a6.js:68:3448)
at t.value (https://tfk.thefreekick.com/assets/application-33e7747c7d87dbd465e8f058373c19dd40307f27fac4d9dca97d7d2565a1f4a6.js:68:1810)
at i (https://tfk.thefreekick.com/assets/vendor-3eae3eec8fba033cb1b5af6c103a5b8781caa69cf97fe7773ba89ba68980b263.js:5:4897)
at r (https://tfk.thefreekick.com/assets/vendor-3eae3eec8fba033cb1b5af6c103a5b8781caa69cf97fe7773ba89ba68980b263.js:5:4810)
at l (https://tfk.thefreekick.com/assets/vendor-3eae3eec8fba033cb1b5af6c103a5b8781caa69cf97fe7773ba89ba68980b263.js:5:8813)
at i (https://tfk.thefreekick.com/assets/vendor-3eae3eec8fba033cb1b5af6c103a5b8781caa69cf97fe7773ba89ba68980b263.js:5:7736)
at r (https://tfk.thefreekick.com/assets/vendor-3eae3eec8fba033cb1b5af6c103a5b8781caa69cf97fe7773ba89ba68980b263.js:5:7663)

Can I bump this and ask the same question - what is causing these log messages?

This appears as a warning in the logs, but the failed to construct message suggests that it should have been a failure.

Background

I’m trying to find the source of an insidious bug on our live system and just want to be able to tick this off the list as not being the cause.

The issue usually presents itself on desktop with multiple tabs open, something is updated (post, like, message) in another tab and the tab you’re in ‘dies’.

Something is causing the browser’s message bus to die which results in the topic’s footer disappearing and the user is left looking at the last post in the topic with no new notifications automatically appearing.

Finding the source of this is proving difficult. I thought I’d removed the plugin(s) that might be responsible but a couple of users are reporting that the issue is still there.

The only thing that I can see in the logs for the time period when they saw the issue is a number of messages about failing to construct Notification.

What have I found about this?

This post on stackoverflow…

…and the referenced chromium bug report, suggests that there is a difference between desktop and mobile Chrome in the way that notifications are handled - and perhaps there is a deprecation issue.

To my untrained eye, it looks like creating a new Notification will work on desktop (but may be deprecated at some point) but will fail on a mobile platform because notifications are implemented differently there.

So if I’m seeing this in the logs, it looks like some desktop code (new Notification) was executed on a device that does not support the creation of notifications in that way - i.e. mobile Chrome.

Indeed, the logs seem to show that the HTTP_USER_AGENT causing this failure are mobile browsers:

  • Mozilla/5.0 (Linux; Android 8.1.0; Moto G (5)) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.105 Mobile Safari/537.36
  • Mozilla/5.0 (Linux; Android 8.0.0; SAMSUNG SM-A750F Build/R16NW) AppleWebKit/537.36 (KHTML, like Gecko) SamsungBrowser/8.2 Chrome/63.0.3239.111 Mobile Safari/537.36

The only code that I can find in my installation using new Notification is in desktop-notifications.js.es6 in core - in the following sections:

and

Some specific questions

What is causing this warning to appear in the logs?

Can I ignore it?

Would it potentially cause the message bus to fail in the way I described above?

1 Like

I can confirm the same thing happens in my community as well.

1 Like

Well, that is interesting.

It seems that the bug I’m chasing could well be related to the “Failed to construct Notification” error.

IF that is the case, I believe that the only place where this piece of code (new Notification) appears is in core Discourse. So it could be a bug in core.

That said, I’m sure more people would be reporting it if this was a problem with core Discourse. So it’s more likely a plugin issue that is breaking core.

Can I ask what non-Discourse plugins you have installed? Let’s see if we can find some common potential cause outside of core.

I don’t have much data on the “Failed to construct” issue at the moment, but what data I have points to a small group of users/devices that are causing the errors.

@thefreekick, how about you?

Do you see anything like the same bug that we’re discussing here?

1 Like

I haven’t seen that happen myself but I’m asking if people have experienced that specific issue.

I haven’t really been able to see a pattern of errors from the user’s point of view other than just some poor topic loading that I’m seeing myself from time to time but not sure if it is related.

The User Agent is showing mobile browsers in the Env for these warnings, similar to your post above.

Happy to explore further if I can be any help - just not really sure how best to troubleshoot.

1 Like

I have two discourse forums. This error appears in both. However in one of them I have hundreds of these errors per hour and I think if its because of a plugin, its because of who is online plugin, which is not installed in the other forum.

Getting the same problem on my instance. Sometimes 30-40 times per day.

TypeError: Failed to construct 'Notification': Illegal constructor. Use ServiceWorkerRegistration.showNotification() instead.
    at https://swapd.co/assets/application-a9a1b96b84ba77c33f26b7f4974eff035fd81fee0da6503e09f7e84e2d2a6b53.js:12:16333
    at h (https://swapd.co/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:18:1869)
    at C (https://swapd.co/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:18:3255)
    at https://swapd.co/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:18:3745
    at e.invoke (https://swapd.co/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:11634)
    at e.flush (https://swapd.co/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:10577)
    at e.flush (https://swapd.co/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:12677)
    at e._end (https://swapd.co/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:17457)
    at MutationObserver._boundAutorunEnd (https://swapd.co/assets/ember_jquery-cf9339810550f9c92505dfbb37362c58a4a8a83bcee2d99174547b01c06ed7d3.js:9:13591)