#956: Early Design Review: Partitioned Popins
Discussions
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Discussed
Aug 1, 2024 (See Github)
Martin: there will be a breakout session in TPAC about this... defer until after that.
Discussed
Oct 1, 2024 (See Github)
no updates
Discussed
Oct 1, 2024 (See Github)
Jeffrey: altetnatives mentioned FedCM, Storage acces, Exemption Heuristics... The question is is there a way to do UI that is clear enough?
Yves: to make sure that people are not tricked.
Jeffrey: that it's not the main origin but that it has access the identity of the origin if there is communicaiton. Not clear that there is any UI that can communicate that. We can ask for solid UX studies that users understand the right thing from some plausable UI...
Dan: user need.
Yves: SSO was listed .. but if fedCM is here then maybe it's not needed?
Peter: the user need is a need for business to maintain their current product... current business model. and i don't think this actually serves... users. It's a dangerous weakening of the web security model and user protections to support a dangerous use case that never should have existed in the use case.
Matthew: they have some UX proposals.. you end up with 2 URL bars ... which is a really really big change... Setting aside the issues they might have about understanding the URL anyway, but having 2 URL bars that would cause implementation pushback...
Dan: the URL is important.
Lea: (1) cookie partitioning and (2) the UI component ... still unclear what that UI is... not sure how these mockups differ from ...
Jeffrey: there's a "please note"...
Lea: what I was going to say is that the most contraversial of the 2 is the whole cookie thing... but not sure why that's needed. None of these address post messages... So why not just use post message? If this is a differnt way to open a popup...
Jeffrey: security benefits to using cookies ... we can make it more secure ... that's some of the motivation here.
Lea: but post message is just used when the popup communicates...
Jeffrey: yes but post message has to go through javascript... This would work without javascript. Core idea is that the authentication token is never exposed to javascript... The context here is that people hire companies to do their login for them - like Octa - so if your site is foo.example, it goes to foo.octa.com ... so it blocks cookies. There have been proposals to use CNAMES and some browsers have taken action to block use of CNAMES for this purpose... Authentication companies are worried about using CNAMEs for this purpose...
Lea: cost / benefit question is open but assuming they are useful - could we layer them differently? What if the different popup UI was a different component?
Jeffrey: example of this in the Arc browser today...
Dan: I've used Octa... I think the use case is valid...
Peter: but the reliance on 3p cookies - which was a bug ... what I'm opposed to is adding features to the web ... that exist purely to support someone's business needs... I have mixed feelings about the CNAME thing... there has been abuse of CNAMEs... fundamentally I get that user authentication is hard - and some people want to outsource that. fine with building a mechanism into the web platform to allow for that. Happy with a dedicated API to do user authentication.
Dan: yes - i agree if we
Lea: I agree it's a common flow - but fedcm us way down the line... Also wondering if the main advantage is the cookie partition thing is to do post message without JS then why not just do that... and the browser takes care of communicating it to those origins... Maybe instead of extending cookies or extending the security model of cookies...
Yves: what you described sounds like first party sets though... so might not be the perfect model... If you're defining what you want to export to another site... content of a header... Also re: fedcm not being implemented... therefore there should be a clear path to deprecating...
Jeffrey: another aspect - it's partitioned - it's not intened to share identities across the 2 sites - it's trying to be like an iframe... a general popup with post message would be too powerful.
Matthew: we discussed when we talked about document PiP that maybe there is a fundamental problem. I like the idea of decoupling UI but in this case since it's privacy maybe not... They compare themselves to fedcm - what about lightweight fedcm?
dan to draft a comment based on above
Discussed
Nov 1, 2024 (See Github)
Jeffrey: they announced a dev trial ...
Jefrey: fedcm is for a 3rd party but this is for using a 3rd party only for authentication - but on behalf of the first party ...
.. the explainer doesn't actually explain the use case...
we discuss CNAMES as an alternate way of supporting an oursourced authentication service
Peter: hard to say CNAMES is a good pattern ...
Hadley: I think there is a clear distinction in the use cases, especially re how much you need to trust the third party. You have to trust whoever is doing your authentication, because they can authenticate as anyone. You don't have to trust you advertisers though -- that's not how the ecosystem works..
Dan: posts comment
Comment by @torgo Nov 11, 2024 (See Github)
The W3C TAG has discussed this proposal and I took an action last week to summarize some of the key points, which I am late on performing - apologies for that. Here are a couple of key points from our discussion:
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Regarding the potential for User Confusion: While UX solutions have been proposed, the effectiveness of these designs in clearly communicating the partitioned nature of identities and data access across origins remains uncertain. Do you have user testing studies that you can share with us which might show how this approach can safeguard against potential user confusion or use in deceptive patterns?
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Regarding Non-JS Communication Alternatives: We noted that the main advantage of Partitioned Popins seems to be allowing secure communication without JavaScript. It may be worth investigating if this benefit can be achieved without the complexities of this approach, such as through a dedicated API or secure post-message alternative that maintains privacy and security integrity.
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We'd like to suggest expanding & clarifying the description of the use case in the explainer.
Comment by @johannhof Nov 22, 2024 (See Github)
Thanks for the feedback @torgo.
- Regarding the potential for User Confusion: While UX solutions have been proposed, the effectiveness of these designs in clearly communicating the partitioned nature of identities and data access across origins remains uncertain. Do you have user testing studies that you can share with us which might show how this approach can safeguard against potential user confusion or use in deceptive patterns?
We are working on this with our UX team and I very much expect them to measure user understanding of the UI that we design for Popins in Chrome. It should be noted that a big motivator for this work comes from the potential user confusion from partitioning traditional popups, which is something we'd like to avoid. We believe that it can only be avoided by introducing a new UI paradigm, and this proposal builds the technical underpinnings for that. There is bound to be some level of uncertainty as we explore this space (it's a bit of a chicken and egg problem, we have to invent and prototype new designs to really measure their effect on users), but I want to make it clear that avoiding user confusion is a key goal for this effort.
- Regarding Non-JS Communication Alternatives: We noted that the main advantage of Partitioned Popins seems to be allowing secure communication without JavaScript. It may be worth investigating if this benefit can be achieved without the complexities of this approach, such as through a dedicated API or secure post-message alternative that maintains privacy and security integrity.
Can you elaborate on "the complexities of this approach", i.e. what is the complexity? I'm not sure how leveraging access to partitioned cookies, which are a simple and secure mechanism (which "maintains privacy and security integrity") and already widely adopted by the ecosystem would be inferior to the development of a new dedicated API.
OpenedMay 14, 2024
こんにちは TAG-さん!
I'm requesting a TAG review of Partitioned Popins.
A new web primitive is needed to cover short-lived popup use cases which require access to storage partitioned by the popup opener. This primitive should be private and secure by default, while providing a consistent UI experience across user agents. To solve this need, we propose the “Partitioned Popin”, a type of pop-up for loading web content with two unique new features: a modal-like UI relative to its opener tab and cookies/storage being partitioned to its opener context.
Further details: