Flow weirdness

demo.js

// FILE ONE
type Return = {
  content: {
    body?: string,
    title: string,
  }
}

const getThread = (id: string): Return => {
  // database.get() returns a promise
  return database.get(id)
}

// FILE TWO
// ...
const thread = await getThread(id); // <= the flow error shows up here - see below
const trimmed = thread.content.body.trim() // <= and not here when calling .trim() on a possibly undefined value
// ...

// Flow error:
/*

Promise (This type is incompatible with the expected param of union: type application of class 'Promise' | 
type parameter 'T' of await Member 1: type application of calss 'Promise' Error: call of method 'trim' 
Method cannot be called on possibly undefined value Member 2: type parameter 'T' of await Error: property 
'channelId' property not found in Promise

*/