[tbb-dev] TargetPrincipalDoesNotMatch message from postMessage in JS Console even though target / recipient origins match.

[Tom Ritter]

Yes, (I'm pretty sure) this is intentional.  I think it's
https://bugzilla.mozilla.org/show_bug.cgi?id=1492607

On Wed, 12 Jun 2019 at 03:47, Dan Bryant <dkbryant at gmail.com> wrote:
>
> Is this an intentional veto of the windows.postMessage API?
> Understandable if it is, but I failed to see where it was implemented
> or how to override it (to re-enable postMessage).
>
> This error shows up when trying to use the TREZOR cryptocurrency
> wallet on https://www.MyCrypto.com (a popular ethereum wallet).  The
> problem arises when www.mycrypto.com tries to authorize through
> connect.trezor.io.  The authorization is performed through
> window.postMessage communication channel.
>
> The text of the error in the JS Console is obviously the
> TargetPrincipalDoesNotMatch message (ref1, line 249).  There is only
> one spot that this message is presented in the postMessage workflow
> (ref2, line 128).  This is only called in a failed equality check,
> which, according to the message text, shouldn't have failed (ref3).
> Since all origins mentioned match "https://connect.trezor.io" I'm
> curious as to why the equality check (ref3, line 96) would have
> failed.
>
> Anyway, I'll be happy to open this as a ticket, I just didn't know if
> this was a known exclusion that is somehow setup upstream of this
> call.
>
> ## JS Console Message
> ---
> Failed to execute ‘postMessage’ on ‘DOMWindow’:
> The target origin provided (‘https://connect.trezor.io’) does not
> match the recipient window’s origin (‘https://connect.trezor.io’).
> ---
>
> ## Reference
> git: https://gitweb.torproject.org/tor-browser.git
> branch: tor-browser-60.7.0esr-8.5-1
> ref1: /dom/locales/en-US/chrome/dom/dom.properties : 249
> ref2: /dom/base/PostMessageEvent.cpp?h=tor-browser-60.7.0esr-8.5-1 : 128
> ref3: /dom/base/PostMessageEvent.cpp?h=tor-browser-60.7.0esr-8.5-1 : 96
> _______________________________________________
> tbb-dev mailing list
> tbb-dev at lists.torproject.org
> https://lists.torproject.org/cgi-bin/mailman/listinfo/tbb-dev