Web Extensions's background page is missing in the Develop -> Web Extension Background Content menu in the latest Safari Technology Preview

Hello! I was wondering if any other developers are experiencing issues with accessing the web extension background script console, sources, etc. on the latest Safari Technology preview or macOS Sequoia betas.

We have an extension which has a persistent background script. In the latest public release of Safari version 17.5 (19618.2.12.11.6) on macOS Sonoma, everything works as expected. When I enable developer mode in Safari, it shows an additional "Develop" menu and when I select "Web Extension Background Content" in the dropdown, it shows a list of background pages for all installed extensions. Attaching a screenshot for reference.

However, if I install the latest Safari Technology Preview 197 on macOS Sonoma or just test with the Safari version that comes with MacOS Sequoia beta 1 or beta 2, the "Web Extension Background Content" dropdown menu does not list any background pages. Attaching a screenshot for reference.

We started discussing the issue with Apple during the latest WWDC. If anyone at Apple sees this post, I opened FB13834388 to track this issue.

However according to Apple, they cannot reproduce the issue exactly as I see it on all macOS machines around me including clean virtual machines, real hardware (MacBook Pro M1 Max, MacBook Air M2, MacBook Pro Intel based). The "Web Extension Background Content" menu looks as expected on their end which is very confusing to me...

I have a reason to believe that new Safari's developer tools are simply broken in the latest release. I base that statement on the fact that I cannot access it in case of our own Safari extension, Apple's sample "Sea Creator" extension and a few random extensions that I got from the App Store.

I was wondering if anyone else can observe the same behavior or all machines around me are haunted :)

Please share if you have similar issues with Safari Technology Preview 197 or Safari on the latest macOS Sequoia beta. Any feedback is important to us. If it's a widespread issue, then Apple should prioritize is accordingly. If the issue is somehow specific to our testing, we will fix it on our side. But any test results at this point are bringing more clarity to the situation and are highly appreciated.

As there is no workaround at present, it would be best to follow up in your bug report.

We are aware of this and working on a fix. I will reach out when we have more information about when the fix will be available.

Web Extensions's background page is missing in the Develop -> Web Extension Background Content menu in the latest Safari Technology Preview
 
 
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