Is dedicating a daily supplication for the deceased through an electronic forum, with members performing the supplication for him, an innovation (bid'ah) or permissible by Sharia?

There is no harm in reminding people to pray for a specific brother, and there is no harm for brothers to pray for him always. However, it is better to generalize the prayer to all believers, for Allah Almighty says: ﴿And those who came after them say, "Our Lord, forgive us and our brothers who preceded us in faith and do not place in our hearts any malice toward those who have believed. Our Lord, indeed You are Kind and Merciful."﴾ [Al-Hashr: 10]. And for the saying of the Prophet, peace and blessings be upon him: "Whoever seeks forgiveness for believing men and believing women, Allah will write for him a good deed for every believing man and woman."