Selection Add Modifier not working/forgotten

[anexistantperson]

If you select an object, hold shift, then try to select another one, it does not add the object to the selection but instead switches to it entirely.

I did ask someone else if they had this problem and they did. I would imagine you have forgotten to fix it or add it at some point if its gone through this many updates without being added.

[Cruor]

Its currently not hooked up, that's why its omitted from the readme currently.

[anexistantperson]

added in new update