Bug 272169 – Enabling Experimental network Loader causes pages to not load

• Component: Page Loading
• Status: RESOLVED FIXED

[Jeffrey Blanz]

When enabling "Enable Experimental Network Loader" in the feature flags of Safari Technology Preview, some websites do not load.

Some courses on https://mylabmastering.pearson.com do not load, while others do. I tested this by enabling and disabling the feature flag. As soon as the flag is disabled the page loads.

[Alexey Proskuryakov]

Thank you for the report! Could you please provide the exact macOS version that you are testing with? 

We do not expect the experimental loader to fully work on any version yet, but it would be good to know if the latest is affected.

Also, if you are aware of any websites that we could test (seems like mylabmastering.pearson.com is limited access), that would be very helpful.

[Jeffrey Blanz]

(In reply to Alexey Proskuryakov from comment #1)
> Thank you for the report! Could you please provide the exact macOS version
> that you are testing with? 
> 
> We do not expect the experimental loader to fully work on any version yet,
> but it would be good to know if the latest is affected.
> 
> Also, if you are aware of any websites that we could test (seems like
> mylabmastering.pearson.com is limited access), that would be very helpful.

I am on macOS 14.5 Beta 1 (23F5049f) and I am using Safari Technology Preview 191.

Yes this one was a weird one. I was not sure if I should even post it, knowing that you basically can't test it.

The only one I website I have trouble with is mylabmastering.pearson.com

I will attach some screenshots of what happens. Note the course name at the top of the screen. The loader works on my CE298 course, but not my MA303 course. I wonder if it has to do with the calendar that the MA303 course has that the CE298 does not.

[Jeffrey Blanz]

Created attachment 470784 [details]
Image of CE298 page loading correctly with the Exp Loader Enabled

[Jeffrey Blanz]

Created attachment 470785 [details]
Image of MA303 page not loading correctly with the Exp Loader Enabled

[Jeffrey Blanz]

Created attachment 470786 [details]
Image of MA303 page loading correctly with the Exp Loader Disabled

[Radar WebKit Bug Importer]

<rdar://problem/126285828>

[Ahmad Saleem]

@Jeffrey - can you share 'Web Inspector' console logs for MA303 page, which fails to load?

Also possibly - if you have any test account to reproduce this issue or any other public website leading to this?

_____

Additionally - can you try to attach 'Web Archive' copy of above page?

Go to File > Save As (from 'Format' drop-down - select 'Web Archive') and upload it as attachment here.

Thanks!

[Jeffrey Blanz]

Created attachment 470898 [details]
Web Inspector of MA303 Page

[Jeffrey Blanz]

Created attachment 470899 [details]
Web Archive of MA303 Page

[Jeffrey Blanz]

I do not have test account as the account I use it tied to my school account. It is also a paid service.

I have yet to find another site that fails to load unfortunately.

[Jeffrey Blanz]

Created attachment 471438 [details]
Video I could not upload

I think I might have accidentally found the cause of this bug, or another bug associated with the experimental network loader.

You cannot upload anything with the experimental network loader enabled.

I could not even upload a video to bugzilla (this site) or Imgur.com.

I will attach the video I could not upload, so that you can try to upload it yourself.

[Jeffrey Blanz]

This happens on macOS, iOS, visionOS, and iPadOS.

[Alexey Proskuryakov]

Inability to upload seems like a separate issue. 

Thank you for the updates - it is known that the experimental loader has bugs in underlying system frameworks in shipping OS versions, so we mostly need to wait for what happens in the future, but it's still good to have a list of things to re-test.

[Alexey Proskuryakov]

We believe the the experimental loader works well in macOS Sequoia, please let us know when/if you have a chance to try it out (will all the warnings about dangers of beta software, of course).

[Jeffrey Blanz]

Created attachment 471644 [details]
Upload test with Experimental Loader enabled on iPhone 13 Pro Max with iOS 18

Upload test with Experimental Loader enabled on iPhone 13 Pro Max with iOS 18

1. If this uploads it is fixed, otherwise you will not see this.

[Jeffrey Blanz]

Fixed on iOS it seems. I will test on macOS later. More hesitant to update that because I do not have access to my external hard drives for a back up right now.

[Jeffrey Blanz]

Created attachment 471666 [details]
macOS Sequoia 15.0 dev beta 1 video upload test

macOS Sequoia 15.0 dev beta 1 video upload test

[Jeffrey Blanz]

I have not found any new issues with macOS Sequoia. The old issues are also gone.

Closing the Post.

[Alexey Proskuryakov]

Thank you for testing!