Agreed.
According to this blog post this is only a temporary work around but the advice that users need to update Firefox by downloading the latest release from a Launchpad or ‘Ubuntu archive’ URL is not a means of receiving updates that Ubuntu users will be used to.
@rs2009, what is your long term solution to this issue given that the Xenial release of Ubuntu will be ‘End of Life’ in April 2021, that the patch to Firefox to support Unity menus is 5200 lines long and hasn’t been part of Firefox in the most recent releases of Ubuntu as Canonical’s Desktop Team have come to the conclusion that it is now too much work to continue supporting?