firefox nightly updates to the version which was latest at the time of the update check, instead of the latest version available at the time that the user consents to the update.

scenario: firefox nightly is left running on friday evening on a computer that is not used over the weekend. when the user unlocks their desktop on monday morning, they see the little green icon telling them an update is available. they trigger the restart-and-update process, wait a few minutes and find that nightly has updated to a version newer than the version left running on friday, but older than the version available at the time that the user triggered the update. the result is that the user must repeat the update process in order to arrive at the latest version.

if possible, it may be a nicer user experience if the updater were to install the latest version available of nightly, instead of requiring the user to install two updates to arrive at the latest version.