This addon restores the old Tab Targeting method that was used prior to the 7.0 legion patch.
Essentially this small addon applies the Cvar change at Player Login and ReloadUI.
/console TargetNearestUseOld 1
Currently if you set the console command it is not saved by the game on next login which is why this addon exists.
There are no options, only a small message printed in the chatlog denoting the addon is loaded.