aaronlbpeterman fixed now, there was apparently a bug where is_donor flag in database was not set for all donors, so I filtered forums by checking whether or not their footer is hidden or not. All donors that donated before 3.0 now have a dummy 7 € donation amount (enough to hide the footer).
In case that you have a PayPal receipt of the donated amount, and your donation would give you higher perks, please E-mail it to email@example.com and we'll fix the donated amount. This is because previously, we didn't keep track of who donated how much.
I am pretty busy right now, but I'll try to make a changelog post here on Discuss this evening