I use Firebase emulator and man that likes to carry on running (or limping?) after Ctrl-C alot, hogging the port so you need to hunt it down and kill it before you can start it again. Both on Linux and Windows.

I think it is a Java (or more to the point JVM) program, not sure if that has anything to do with it. In addition I believe it is a lot of parallel programs running at once, or they could be different threads. As there are lots of Firebase services it needs to emulate.