Library Output should have checkbox option that will allow it to not over-write ports that have no information on export.
Library Output is very useful when you use it as a quick checkpoint for saving files. But is uncofortable when you want to use only on of it. Because after desabling one of inputs, after export it will replace information in file related to this input with nothing. Soooooooo, it maybe very comfortable to have option to prevent this behavior. So, when you exported one input and disabled it, you will allow to use Library Output for other inputs without deteleting information from disabled inputs.
Maybe screenshot can explain more - those Library Outputs exactly the same. If you will export left one and than export right one, it will ruine all infortmation inside of a file and overwrite it with nothing. Also wotks if you have connected wires that have disabled devices.
Update, guys: I fixed it with this idea, lol, they just use same file
Update#2: NONONONONONONONONONONOONONONON GUYS IT IS VERY BAD IDEA I JUST ACCIDENTALLY OVERWRITED FULL MAP WITH LITTLE PIECE OF IT AND NOW I’M CRYING 
developer must to add this feature 
