inv-save

A small modthat has three commands - invsave - which is enabled by default(function of the mod), invsave_offhand - which is enabled by default, and invsave_amount - which is set to 4 by default
This means the first four items in your hot bar, along with your armor(also first 4 slots some reason) and your offhand will stay with you when you die
How to configure!
Singleplayer: open to lan -> turn on cheats -> change the config to how you want it (/gamerule invsave -> reload your world to disable cheats
Multiplayer: be an operator -> /gamerule invsave -> done
the three commands are.
/gamerule invsave
/gamerule invsave_offhand
/gamerule invsave_amount