Re: [presentation-api] Clarify behavior when the receiving page attempts to navigate itself (#455)

Spec comments:
- Our spec should reference the _allowed to navigate_ algorithm in HTML because we already referencing the _sandboxed top-level navigation browsing context flag_ that is used by it. 
- However presentation receivers also block self-navigation, which has no equivalent in HTML.  The spec should be clear this is an additional condition on top of HTML _allowed to navigate_.

Implementation comments:
- Because there is no flag in HTML for the self-navigation case, aborting navigation or throwing is more challenging.
- I don't see a strong use case for receiving user agents offering to open in a new window, but no reason to block it.
- Therefore, in the spec I recommend that the behavior for blocked navigation SHOULD be consistent with HTML.

I can put together a PR along these lines for review.

In the long run, this requirement may be too restrictive.  For example, in Chrome PWA's are allowed to self-navigate within their URL scope without showing an address bar.   We should think about the tradeoffs here.



-- 
GitHub Notification of comment by mfoltzgoogle
Please view or discuss this issue at https://github.com/w3c/presentation-api/issues/455#issuecomment-479688437 using your GitHub account

Received on Wednesday, 3 April 2019 22:59:02 UTC