SeaMonkey would be good if it weren't for modern websites being well, modern websites, and both Mozilla, with their decision to cut SeaMonkey off most of their infrastructure... and later on PaleMoon with its endless barrage of drama and pandering-but-actually-not to the 'uwu windows xp!!11!1! le fruitger aro y2k' crowd... pretty much screwing them over into irrelevance.