Some replay viewer tool, shows chat, named pings, positions on a preview map and also lots of detailed info mainly for debugging replay (loads last replay on default).. you can view the entire command stream, header, treeview on objects in the replay..
Also you can view single player replays with FAF autopatching by converting and starting them via [Launch as .fafreplay] button. This would also work for 3599, or any other SCFAReplay if FAF adds autopatching support for it.