future perfect simple question

In the English Grammar Profile, C2 point 70 in the category of FUTURE is

future perfect simple QUESTIONS:

For example:

Will they have learned that reading is a chore?

A COCA search for:

Will _P have _V*N *

This is extremely rare!

1 WILL WE HAVE LEFT 4
2 WILL WE HAVE MADE 4

  The Cornell Daily Sun

When our other friend calls Trump voters ” insane ” and we don’t disagree with them, how will we have made this friend feel?

18 Nov 2020

3 WILL YOU HAVE TAKEN 3
4 WILL YOU HAVE LEFT 3
5 WILL YOU HAVE ACHIEVED 3

  92moose.fm

Why I Stopped Getting Angry About Shoes in The Entryway

And what will we have left?

*This example is ambiguous and might not be future perfect.  ‘left’ might be functioning here as a participle/adjective as in ‘we had nothing left.  There was no leftover food.’  Another rewording might be ‘What will we have that is left over?‘