Allow sites to define friend domains

[sohomdatta1]

In certain cases, multiple sites/origins could be owned by the same org (ex: *.wikipedia.org and *.wikisource.org or *.google.com and *.withgoogle.com). Could we provide some (opt-in) way/mechanism for a site to define other sites to with which :visited link data can be shared?

[NDevTK]

The example of "*.google.com and *.withgoogle.com" would probably be bad since I think they use separate domains for isolation.
That said sites can always "opt-in" to sharing visited links the fun way via postMessage and iframes.

[sohomdatta1]

@NDevTK I think they use *.googleusercontent.com for sandboxing, *.withgoogle.com is (AFAIK) used for hosting websites/events related to Google (ex: https://capturetheflag.withgoogle.com/ )

[NDevTK]

At least from what I can tell *.withgoogle.com hosts less sensitive applications such as event pages.

[sohomdatta1]

At least from what I can tell *.withgoogle.com hosts less sensitive applications such as event pages.

Yep that's a good point, whatever mechanism is implemented should probably be only one-way (*.withgoogle.com can share its data with *.google.com but unless *.google.com consents, *.withgoogle.com should not be allowed to read the visited data of *.google.com)

[miketaylr]

@sohomdatta1 could you expand on the use case a bit more? I'm having a hard time understanding how this would be useful. Thanks!

[sohomdatta1]

@sohomdatta1 could you expand on the use case a bit more? I'm having a hard time understanding how this would be useful. Thanks!

Sure, I've put together a user-story/example of where it would be useful :)

Imagine I'm a user who loves reading wikipedia articles and I have already read the article Rabindranath Tagore. Now, I discover en.wikisource.org (which is owned by the same company, Wikimedia Foundation) and come across this page that lists all the works of the author, Rabindranath Tagore. At the top, it also links to the article on Rabindranath Tagore on en.wikipedia.org.

Under the current restrictions, this link would not be surfaced as visited (since I haven't actually visited the page from en.wikisource.org, but have done so from en.wikipedia.org) however, if we could allow sharing of link information between trusted sites, interwiki links (which are what these kinds of links are called in the Wikimedia community) would show up as visited if both *.wikisource.org and *.wikipedia.org agree (which I assume would be easy since both the websites are owned by the same parent organization).