There is unbranded thunderbird and firefox in portage, but it isn't the same as IceCat and IceDove, so maybe there should be a seperate ebuild for it. Reproducible: Always
There's exactly one active mozilla herd member to take care of the whole mozilla shebang. Sorry but we have absolutely no resources to introduce some 'forks' into the tree.
Firstly, I think this bug would be worth leaving open were it not for the fact that it contained two software packages in the same bug report. This would have needed to be filed as two separate bugs so that progress on each could be tracked *separately*. Please never put ebuild requests for more than one software package in the same bug. Having said that, the sping overlay now has some ebuilds: http://gpo.zugaina.org/www-client/icecat. Were this bug filed only for icecat, we could have marked #233164 as a duplicate, but this should remain closed (or perhaps changed to invalid).