User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:65.0) Gecko/20100101 Firefox/65.0

Steps to reproduce:

With handoff enabled on a macOS device (let's call this "DeviceA"), open a new webpage in Firefox and attempt to continue viewing the page on another handoff enabled device ("DeviceB") logged into the same iCloud account.

Actual results:

We are not able to continue viewing the webpage on "DeviceB" as macOS Firefox does not support sending handoff requests (only receiving is supported as of Firefox 65 see https://bugzilla.mozilla.org/show_bug.cgi?id=1085391#c8).

Expected results:

When viewing a webpage on macOS Firefox, a user should be able to continue viewing the webpage on other Apple devices through handoff.

For more info about handoff:
https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/Handoff/HandoffFundamentals/HandoffFundamentals.html#//apple_ref/doc/uid/TP40014338-CH3-SW1

This is a feature request that I personally want and am willing to work on, however, implementing this will require Firefox to push browsing information (like the URL a user is currently visiting) out through Apple services.

I'm not sure if implementing this feature will then be a privacy/legal issue? Does anyone have a suggestion on how I can determine whether this functionality would be accepted and merged? Is any of the Mozilla legal team present on bugzilla?

This is one article that I've found so far regarding handoff security (although it's not official Apple documentation, so it's not something that should be 100% relied on) https://www.imore.com/how-apple-keeps-your-handoff-data-secure

Depends on D129405

https://hg.mozilla.org/mozilla-central/rev/ef4d020c711d

I have attempted to verify this implementation between two Macs, specifically between MacBook Air mid-2013 (11.6.2) and MacMini mid-2011 (10.13.6), however, I could not even make it work between Apple applications, after reading an article that pointed to the fact that the 2011 MacMini is compatible with Apple Handoff.

Furthermore, I've found more articles (ex) that it was only oficially supported on 2012 and later Minis. I've also tried to force it work by this article, but the steps could not be completed.

To help the other tester that attempts verification of this implementation:
https://support.apple.com/en-us/HT209455 - how it works
https://support.apple.com/en-us/HT204689 - supported devices

Important to note: this feature was created especially to work between Macs and iOS devices, not between macs so it would be best if the verification was done by the mobile team.

Verifying as fix on Firefox 96.0 release and beta 97.0b2 on macOS 10.15.7. After visiting a page in Firefox on iOS device the hand-off is correctly received on desktop. Tapping on the hand-off icon from the toolbar will open the page from iOS in the desktop default browser.

(In reply to Simon Basca [:SimonB] from comment #7)

Verifying as fix on Firefox 96.0 release and beta 97.0b2 on macOS 10.15.7. After visiting a page in Firefox on iOS device the hand-off is correctly received on desktop. Tapping on the hand-off icon from the toolbar will open the page from iOS in the desktop default browser.

As I understand, this issue is about macOS Firefox being able to send handoff requests to other devices, e.g. to Safari on iOS. It seems to me you tested handoff in the opposite direction which has been implemented long time ago as stated in the original post.

(In reply to Michał Gołębiowski-Owczarek [:mgol] from comment #8)

(In reply to Simon Basca [:SimonB] from comment #7)

Verifying as fix on Firefox 96.0 release and beta 97.0b2 on macOS 10.15.7. After visiting a page in Firefox on iOS device the hand-off is correctly received on desktop. Tapping on the hand-off icon from the toolbar will open the page from iOS in the desktop default browser.

As I understand, this issue is about macOS Firefox being able to send handoff requests to other devices, e.g. to Safari on iOS. It seems to me you tested handoff in the opposite direction which has been implemented long time ago as stated in the original post.

Michal sorry for the confusion. I can confirm that hand off is working correctly both ways:
Case 1:

• Opening a page on iPhone 12 Pro (15.2) in Firefox iOS 96.0 (7403) can be correctly opened on macOS 10.15.7. via Hand off

Case 2:

• Opening a webpage on macOS 10.15.7. can be opened correctly on iPhone 12 Pro (15.2) via Hand off.

Note:

• For case 2), the page shared from desktop is always opened in Safari on iOS, regardless of the default browser.
• Hand off is not fully supported in Firefox iOS (https://github.com/mozilla-mobile/firefox-ios/issues/9513)

Let me know if there is any more testing required on this issue.