[Violation] Permissions policy violation: unload is not allowed in this document.

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[Violation] Permissions policy violation: unload is not allowed in this document.

Sue Faye 0

Hi, currently Edge devTools getting [Violation] Permissions policy violation: unload is not allowed in this document.

I have tried to figure out, it come from ScriptResource
User's image
is it because of the deprecating the unload event? Any suggestion on it?

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Answer 1

Carl-L 22,915 Microsoft External Staff Moderator

Hello Sue Faye,

Welcome to Microsoft Q&A forum.

Yes, based on your photos, this likely comes from the decrepitation of unload event. As I see, MicrosoftAjax.js is attempting an unload event which is blocked. Also, this is an action from the Chromium core, so it should be applied to all users using this, not just Edge,

If you are just watching the code and the website is still function normally, I'd suggest let it be, this just act as a simple warning. However, if you are controlling the code, I'd suggest remove the dependencies from window.addEventListener("unload", ...) and find a replacement, depends on what the handler do.

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Sue Faye 0 Reputation points

2026-09-22T07:13:49.6266667+00:00
Hi, we are maintaining .NET framework 4.8 web application that use ScriptManager and UpdatePanel.

MicrosoftAjax.js**
**MicrosoftAjaxWebForms.js

From my understanding, these JavaScript files are not physical files in the project

Questions

Is MicrosoftAjax.js embedded in System.Web.Extensions and dynamically served via ScriptResource.axd by ScriptManager?

Is MicrosoftAjaxWebForms.js also generated from the same assembly and loaded automatically for UpdatePanel / PageRequestManager?

Is there any supported way to prevent the framework from registering the window.unload handler without removing ScriptManager or UpdatePanel?

Has Microsoft released any update or guidance for this unload registration in modern Chromium/Edge browsers?
Carl-L 22,915 Reputation points Microsoft External Staff Moderator

2026-09-23T10:16:55.8+00:00

Hello Sue Faye,

Thanks for replying.

I'll see what I can do. I'll keep you updated.
Carl-L 22,915 Reputation points Microsoft External Staff Moderator

2026-09-24T09:27:00.8133333+00:00
Hello Sue Faye,

Thanks for your patience.

Regarding your questions, I'll answer them in order.

Yes, ScriptManager belongs to System.Web.Extensions.dll, and its role is to manage ASP.NET AJAX script libraries.

When partial-page rendering is enabled, the answer is yes. You can find more information about thse questions in this article.

There is a few ways to do so, replacing the scripts is an example. But right now, I can't seem to find any supported fixes for it. Same goes for question 4.
Carl-L 22,915 Reputation points Microsoft External Staff Moderator

2026-09-25T10:17:14.67+00:00

Hello Sue Faye,

Just checking in to make sure that you have received my reply. Please let me know if you have any updates.
Sue Faye 0 Reputation points

2026-09-28T01:21:30.9733333+00:00

Thank you for your clarification.

Just to confirm my understanding of question 3: replacing the Microsoft AJAX scripts is one possible approach, but there is currently no official or supported replacement script from Microsoft that removes the window.unload registration. Is that correct?

If there are any updates, patches, or official guidance from Microsoft in the future, please keep me updated.

Thank you!
Carl-L 22,915 Reputation points Microsoft External Staff Moderator

2026-09-29T13:44:14.13+00:00

Hello Sue Faye,

Yes, as far as I know, the method itself is possible, but there is no current supported way documented, so if you want to go along with it, proceed at your own risk.

Thank you for your understanding.

[Violation] Permissions policy violation: unload is not allowed in this document.

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