The South Coast club finally received the go ahead on Friday from Deputy Prime Minister John Prescott to build a new stadium at Falmer on the outskirts of the city after a six-year battle.
Their biggest crowd of the season at Withdean, the converted athletics stadium which acts as Brighton's temporary home, were hoping to celebrate the news with a second home win of the campaign - but Ipswich put a stop to that.
Everything seemed to be going according to plan for Brighton when Dean Hammond opened the scoring in the 15th minute with a goal worthy of the occasion.
A cross-field pass by Leon Knight found Colin Kazim-Richards on the right wing and his pinpoint cross was met by Hammond with a side-foot into the roof of the net from 12 yards.
Brighton could have added to Hammond's third goal of the season, Alexandre Frutos going close with a header and then a free-kick which was palmed away by Ipswich goalkeeper Lewis Price.
The match turned in the 32nd minute when Brighton lost captain Charlie Oatway, who was stretchered off with a neck injury sustained in a challenge by Jimmy Juan, which earned the Ipswich midfielder a booking.
At the same time the visitors brought on Jim Magilton, their skipper and midfield playmaker, in place of Matt Richards, with Darren Currie reverting to his customary role on the left.
The move paid off as Sam Parkin levelled for the visitors in the 39th minute with a glancing header from a Fabian Wilnis cross.
Both sides were denied by the woodwork in the second half, when Ipswich improved and Brighton's first-half superiority waned.
Parkin headed against the crossbar from Currie's free-kick two minutes after the restart, before Knight crashed a shot against the underside of the Ipswich bar from the edge of the area midway through the second period.
Brighton had chances to take all three points late on, substitute Jake Robinson missing the best of them with a tame effort easily saved by Price.