Maybe enable the cookie banner service and UI

In #42026 (closed) we disabled the cookie banner service and its UI out of caution. We want to use the 13.5 alpha cycle to better assess its security and privacy implication and possibly enable it, since it's a desirable feature from our UX stand-point.

added 13.5 stable Fingerprinting labels

assigned to @ma1

marked this issue as related to #42026 (closed)

mentioned in issue #42026 (closed)

mentioned in merge request !794 (merged)

added Roadmap::Future label

added All Platforms label

added Feature label

removed 13.5 stable label

added 14.5 stable label

With firefox 120, this became enabled in germany. And I think it is in the current firefox beta for everyone. I think it just missed full roll-out to ESR 128 though.

Some potential issues with Tor Browser:

1. Do we want to show the UI to disable this feature? It would potentially identify the user.
2. At least in earlier implementations, the banner clicker would sometimes choose to accept cookies instead of rejecting them. Are we allowed to make this decision for a user (including legally) if they have no indication that this is happening.
3. Can the user make a temporary exception for a single site? E.g. if some site functionality is lost by rejecting.

An alternative would be to rely on ublock's cookie banner rules once ublock is integrated.

removed 14.5 stable label

changed title from Enable the cookie banner service and UI to Maybe enable the cookie banner service and UI

added Apps::Type::Investigation label

added Apps::Impact::Unknown label