Bugzilla

### Beta/Release Uplift Approval Request
* **User impact if declined**: Cookies may be missing from download requests triggered by extensions, and potentially result in incorrect downloads. This is a recent regression in Firefox 80 - bug 1658673 - https://bugzilla.mozilla.org/show_bug.cgi?id=1658673#c6 . This scenario is now covered by extensive unit tests.
* **Is this code covered by automated tests?**: Yes
* **Has the fix been verified in Nightly?**: No
* **Needs manual test from QE?**: No
* **If yes, steps to reproduce**: 
* **List of other uplifts needed**: 1621249  - This introduced new unit tests with test coverage for this feature, with a TODO that is addressed by this patch.
* **Risk to taking this patch**: Low
* **Why is the change risky/not risky? (and alternatives if risky)**: The change is in a specific part of the download implementation and has been covered by unit tests.
The effect of the change is that relevant "third-party" cookies are added to extension-initiated download requests,
and generally to all "save as" downloads triggered from the browser, even when tracking protection is configured to be very strict (e.g. blocking all third-party cookies).
* **String changes made/needed**:

### Beta/Release Uplift Approval Request
* **User impact if declined**: Cookies may be missing from download requests triggered by extensions, and potentially result in incorrect downloads. This is a recent regression in Firefox 80 - bug 1658673 - https://bugzilla.mozilla.org/show_bug.cgi?id=1658673#c6 . This scenario is now covered by extensive unit tests.
* **Is this code covered by automated tests?**: Yes
* **Has the fix been verified in Nightly?**: No
* **Needs manual test from QE?**: No
* **If yes, steps to reproduce**: 
* **List of other uplifts needed**: bug 1621249  - This introduced new unit tests with test coverage for this feature, with a TODO that is addressed by this patch.
* **Risk to taking this patch**: Low
* **Why is the change risky/not risky? (and alternatives if risky)**: The change is in a specific part of the download implementation and has been covered by unit tests.
The effect of the change is that relevant "third-party" cookies are added to extension-initiated download requests,
and generally to all "save as" downloads triggered from the browser, even when tracking protection is configured to be very strict (e.g. blocking all third-party cookies).
* **String changes made/needed**: