The mod Jetpack (0.4.7) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event jetpack::jetpack (ID 275)
Error when running interface function minime.on_character_swapped: LuaEntity API call when LuaEntity was invalid.
stack traceback:
[C]: in function 'index'
minime/scripts/player.lua:721: in function 'update_armor'
minime/scripts/remote_interface.lua:300: in function <minime/scripts/remote_interface.lua:246>
stack traceback:
[C]: in function 'call'
jetpack/control.lua:18: in function 'raise_event'
jetpack/scripts/jetpack.lua:760: in function <jetpack/scripts/jetpack.lua:560>
(...tail calls...)
jetpack/scripts/jetpack.lua:915: in function 'start_on_character'
jetpack/scripts/jetpack.lua:1049: in function 'toggle'
jetpack/scripts/jetpack.lua:1082: in function 'callback'
jetpack/scripts/event.lua:14: in function <jetpack__/scripts/event.lua:12>

Thanks for the report, I've already fixed that for the next version. Until then, it should be safe to delete line 721 of scripts/player.lua.

Please try out version 2.0.13!