Hello,

As of writing, the official "Privacy Sandbox feature status" article 
<https://privacysandbox.google.com/overview/status> includes a table 
"Fenced Frames" status as "Continue to support" and then later down lists 
it as "In general availability in Chrome.". The article includes timestamp 
"Last updated: October 17, 2025" so it was written before Fenced Frame API 
specification was archived on GitHub 
<https://github.com/WICG/fenced-frame/commit/1133dcaa93be2d934cfa9c704b4e42875107b550>
 
on February 15, 2026. Perhaps, this article could be updated to communicate 
deprecation?

Thanks,
Anton.
On Thursday, August 13, 2026 at 8:11:33 PM UTC+3 [email protected] wrote:

> This answers the question, thank you.
>
> Does M154 also come with a deprecation warning or is this just going be a 
> silent stub? I'm curious if there is some forcing function for developers 
> to realize that this is going to be removed in M155?
>
> Thanks,
> Vlad
>
> On Thu, Aug 13, 2026 at 12:42 PM Shivani Sharma <[email protected]> 
> wrote:
>
>> Yes, the Fenced Frames use counter 
>> <https://chromestatus.com/metrics/webfeature/timeline/popularity/284> 
>> shows usage on approximately 0.07% of page loads.
>>
>> Note that this counter tracks the instantiation of the <fencedframe> 
>> element rather than successful navigation. Since the default URL mode (via 
>> new FencedFrameConfig(url)) has always been disabled by default on Stable, 
>> and the navigation APIs (runAdAuction and selectURL) are already stubbed 
>> and being removed (a precondition to FF's stubbing and removal), these 
>> elements can no longer navigate (internal UMA metrics confirms that).
>>
>> Regarding the concern about breaking feature detection: Websites cannot 
>> rely solely on the existence of window.HTMLFencedFrameElement to assume 
>> Fenced Frame navigations will succeed. For example, if a user disables the 
>> Privacy Sandbox via Chrome settings, the HTMLFencedFrameElement interface 
>> remains defined on the window, but the APIs to obtain a navigation config 
>> (runAdAuction, selectURL) return null or reject. Websites already must 
>> handle this case gracefully.
>>
>> Staged removal via stubs and Finch: If we remove the element completely 
>> immediately, it will resolve to HTMLUnknownElement. This causes it to lose 
>> its default 300x150 sizing, collapsing to 0x0 unless explicitly sized in 
>> CSS. Staging this transition—keeping it as a stub in M154 and rolling out 
>> the element removal via Finch in M155—allows a gradual transition, rather 
>> than risking sudden layout regressions for 100% of Stable users at once.
>>
>> Also a correction on the original intent mentioning stubbing the 
>> `fenced-frame-element.config.setSharedStorageContext()` API but that would 
>> not be needed since shared storage removal will remove that (tracking bug 
>> <https://issues.chromium.org/545349630>).  
>>
>> Please let me know if this answers the question.
>>
>> On Wed, Aug 12, 2026 at 11:43 AM Vladimir Levin <[email protected]> 
>> wrote:
>>
>>> Do you have use counter numbers by any chance?
>>
>>
>>> I also have some concern about the plan here. Removing the feature but 
>>> keeping the idl as stubs for a release sounds like it would break feature 
>>> detection. Specifically, one could detect that these APIs exist but they do 
>>> nothing. Can you comment on that? I'd almost want to see a faster removal 
>>> after a deprecation period, assuming use counters are low enough.
>>>
>>
>>> Thanks!
>>> Vlad
>>>
>>> On Tuesday, August 11, 2026 at 4:20:44 PM UTC-4 Shivani Sharma wrote:
>>>
>>>> *[Adding summary again with formatting since chromestatus formatting 
>>>> didn't work]*
>>>>
>>>> *Summary*
>>>> Fenced frames are nested frames that embed content onto a page without 
>>>> the ability to share data between the fenced frame and its embedder. 
>>>>
>>>> window.fence APIs include Fenced frames Ads reporting (FFAR) JS APIs 
>>>> that were created for privacy-safe ads reporting from FFs created using 
>>>> Protected Audience and SelectURL and getNestedConfigs() to support PA 
>>>> component ads. 
>>>>
>>>> This intent is for removing both of these. Fenced frames element 
>>>> removal will be two step as detailed below. 
>>>> With the removal (or stub API replacement) of PA and selectURL, FFs can 
>>>> no longer be navigated and thus it is safe to remove them. 
>>>>
>>>> Fenced frames are only able to be navigated using the urn:uuid in a 
>>>> FencedFrameConfig[1], which can only be created using the return values 
>>>> from runAdAuction and selectURL. These APIs are being deprecated and 
>>>> removed in M152 as per the following Intent threads: Protected 
>>>> Audience[2], 
>>>> Shared Storage[3]. 
>>>>
>>>> Plan: Given that the fenced frames element can no longer be navigated, 
>>>> we propose removing the element from the code in the following phases: 
>>>> 1. M154: Keep the fenced frame element and its associated IDL 
>>>> dependencies as stubs. This is to ensure no JS call throws, e.g.calling 
>>>> fenced-frame-element.config.setSharedStorageContext(). 
>>>> 2. M154: In the same milestone we will also remove the window.fence 
>>>> APIs completely. Since there is no FF document navigation, these APIs 
>>>> cannot be invoked anymore, so it will be a no-op. 
>>>> 3. M155 Canary/Beta: Begin a controlled rollout of the stub FF HTML 
>>>> element removal via a field trial. Note that removing the element will 
>>>> resolve it to HTMLUnknownElement. 
>>>> At this point we are requesting approvals for all of the above steps. 
>>>> 4. M155 Stable: Assuming there are no regressions or breakage after 
>>>> reaching 1% stable, we will request additional approval for full removal 
>>>> of 
>>>> the FF element. 
>>>>
>>>> [1]
>>>> https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/core/html/fenced_frame/fenced_frame_config.idl
>>>>  
>>>> [2]
>>>> https://groups.google.com/a/chromium.org/g/blink-dev/c/k_nubsMb97g/m/awPD4IGLBAAJ
>>>>  
>>>> [3]
>>>> https://groups.google.com/a/chromium.org/g/blink-dev/c/uh5Ke6qyegc/m/WFTFnhyJBAAJ
>>>>
>>>> On Tue, Aug 11, 2026 at 4:17 PM Chromestatus <
>>>> [email protected]> wrote:
>>>>
>>>>> *Contact emails*
>>>>> [email protected], [email protected], [email protected]
>>>>>
>>>>> *Explainer*
>>>>> https://github.com/WICG/fenced-frame/blob/master/explainer/README.md
>>>>>
>>>>> *Specification*
>>>>> https://wicg.github.io/fenced-frame 
>>>>>
>>>>> *Summary*
>>>>> Fenced frames are nested frames that embed content onto a page without 
>>>>> the ability to share data between the fenced frame and its embedder. 
>>>>> window.fence APIs include Fenced frames Ads reporting (FFAR) JS APIs that 
>>>>> were created for privacy-safe ads reporting from FFs created using 
>>>>> Protected Audience and SelectURL and getNestedConfigs() to support PA 
>>>>> component ads. This intent is for removing both of these. Fenced frames 
>>>>> element removal will be two step as detailed below. With the removal (or 
>>>>> stub API replacement) of PA and selectURL, FFs can no longer be navigated 
>>>>> and thus it is safe to remove them. Fenced frames are only able to be 
>>>>> navigated using the urn:uuid in a FencedFrameConfig[1], which can only be 
>>>>> created using the return values from runAdAuction and selectURL. These 
>>>>> APIs 
>>>>> are being deprecated and removed in M152 as per the following Intent 
>>>>> threads: Protected Audience[2], Shared Storage[3]. Plan: Given that the 
>>>>> fenced frames element can no longer be navigated, we propose removing the 
>>>>> element from the code in the following phases: 1. M154: Keep the fenced 
>>>>> frame element and its associated IDL dependencies as stubs. This is to 
>>>>> ensure no JS call throws, e.g.calling 
>>>>> fenced-frame-element.config.setSharedStorageContext(). 2. M154: In the 
>>>>> same 
>>>>> milestone we will also remove the window.fence APIs completely. Since 
>>>>> there 
>>>>> is no FF document navigation, these APIs cannot be invoked anymore, so it 
>>>>> will be a no-op. 3. M155 Canary/Beta: Begin a controlled rollout of the 
>>>>> stub FF HTML element removal via a field trial. Note that removing the 
>>>>> element will resolve it to HTMLUnknownElement. At this point we are 
>>>>> requesting approvals for all of the above steps. 4. M155 Stable: Assuming 
>>>>> there are no regressions or breakage after reaching 1% stable, we will 
>>>>> request additional approval for full removal of the FF element. [1]
>>>>> https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/core/html/fenced_frame/fenced_frame_config.idl
>>>>>  
>>>>> [2]
>>>>> https://groups.google.com/a/chromium.org/g/blink-dev/c/k_nubsMb97g/m/awPD4IGLBAAJ
>>>>>  
>>>>> [3]
>>>>> https://groups.google.com/a/chromium.org/g/blink-dev/c/uh5Ke6qyegc/m/WFTFnhyJBAAJ
>>>>>  
>>>>>
>>>>> *Blink component*
>>>>> Blink>FencedFrames 
>>>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EFencedFrames%22>
>>>>>
>>>>> *Web Feature ID*
>>>>> *No information provided* 
>>>>>
>>>>> *Motivation*
>>>>> As described in the summary section, since fenced frames are no longer 
>>>>> able to be navigated to a document, once PA and selectURL are removed, we 
>>>>> should also remove FFs API for code health and to remove unused APIs from 
>>>>> the web platform. 
>>>>>
>>>>> *Initial public proposal*
>>>>> *No information provided*
>>>>>
>>>>> *TAG review*
>>>>> *No information provided* 
>>>>>
>>>>> *TAG review status*
>>>>> Not applicable
>>>>>
>>>>> *Goals for experimentation*
>>>>> None 
>>>>>
>>>>> *Risks*
>>>>>
>>>>>
>>>>> *Interoperability and Compatibility*
>>>>> Since fenced frames were not implemented by other browser vendors, 
>>>>> there is no interoperability risk. Removing fenced frames is backward 
>>>>> compatible once PA and selectURL have been removed since FFs can then no 
>>>>> longer be navigated to a document. But there may be minor inconsistencies 
>>>>> b/w FF element and HTMLUnknownElement, e.g. their default size so we plan 
>>>>> to keep FF element as a stub and remove the stub via field trial. 
>>>>>
>>>>> *Gecko*: No signal
>>>>>
>>>>> *WebKit*: No signal
>>>>>
>>>>> *Web developers*: No signals
>>>>>
>>>>> *Other signals*:
>>>>>
>>>>> *WebView application risks*
>>>>>
>>>>> Does this intent deprecate or change behavior of existing APIs, such 
>>>>> that it has potentially high risk for Android WebView-based applications? 
>>>>> *No information provided* 
>>>>>
>>>>>
>>>>> *Debuggability*
>>>>> We will add an issue to dev tools when FF is converted to a stub 
>>>>> element, whenever a FF element is created, that they will be removed 
>>>>> shortly. 
>>>>>
>>>>> *Will this feature be supported on all six Blink platforms (Windows, 
>>>>> Mac, Linux, ChromeOS, Android, and Android WebView)?*
>>>>> Yes
>>>>>
>>>>> *Is this feature fully tested by web-platform-tests 
>>>>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>?*
>>>>> Yes 
>>>>>
>>>>>
>>>>> *Flag name on about://flags*
>>>>> *No information provided* 
>>>>>
>>>>> *Finch feature name*
>>>>> *No information provided* 
>>>>>
>>>>> *Non-finch justification*
>>>>> *No information provided*
>>>>>
>>>>> *Rollout plan*
>>>>> Will ship enabled for all users
>>>>>
>>>>> *Requires code in //chrome?*
>>>>> False
>>>>>
>>>>> *Tracking bug*
>>>>> https://issues.chromium.org/538634423
>>>>>
>>>>> *Estimated milestones*
>>>>> Shipping on desktop 154 
>>>>> Shipping on Android 154 
>>>>> Shipping on WebView 154 
>>>>>
>>>>> *Anticipated spec changes*
>>>>>
>>>>> Open questions about a feature may be a source of future web compat or 
>>>>> interop issues. Please list open issues (e.g. links to known github 
>>>>> issues 
>>>>> in the project for the feature specification) whose resolution may 
>>>>> introduce web compat/interop risk (e.g., changing to naming or structure 
>>>>> of 
>>>>> the API in a non-backward-compatible way). 
>>>>> *No information provided*
>>>>>
>>>>> *Link to entry on the Chrome Platform Status*
>>>>> https://chromestatus.com/feature/6366274495053824?gate=5364408546099200
>>>>>
>>>>> This intent message was generated by Chrome Platform Status 
>>>>> <https://chromestatus.com>. 
>>>>>
>>>>

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