On add new item into "ObservableMap", functional component is not re rendering when the accessing item is dynamically created

[muneerashaik]

Facing Issue:

I am using an observable map to store the tasks. I have a use case where the task is added dynamically after accessing it.
I have an "arrow function" and "normal function" in my store to access the item. When I use "normal function", rendering is as expected otherwise there is no re-rendering happening

How to reproduce the issue:

The minimal example to reproduce the issue
https://codesandbox.io/s/flamboyant-lake-r34r1x?file=/src/App.tsx

Steps to follow to reproduce:

• There are two methods in TaskStore
  1. getTask
  2. getTaskArrowFunction
• if we use getTask getting issue

Mobx versions:

• "mobx": "5.15.0",
• "mobx-react": "6.1.4"

[urugator]

Action's are for mutating state, not for reading it as part of derivations (observer/autorun/computed/etc).