Battery draining overnight

There are no easy answers. If you think it is the dome circuit, chase it down. Start by making certain the vehicle does not have a trunk light stuck on, underhood lamp or the glove box lamp. If you can kill it by removing fuses, look up in the service manual to find a list of items on that particular fuse. One you for certain know what circuit or fuse that it's on, you can go from there

There are "tricky" ones, AKA an alternator can develop leaky diodes, and it is connected at all times and not fused. So to "catch" it as a leak, you just have to unhook the charge wire and see fi the load goes away

The OEM radio is a rare possibility, but could happen, and ANY modern stereo is a possibility due to problems in the memory "keep alive circuit, OR THE AUDIO OUTPUT transistors, which are connected all the time