>> 1. emacs -Q
 >> 2. (setq ibuffer-default-shrink-to-minimum-size t)
 >> 3. M-x ibuffer-other-window
 >> 4. *Ibuffer* isn't shrinked
 >>
 >> [Because ibuffer-auto-mode is not bound and hence fit-window-to-buffer
 >> is not called.]
 >
 > Thanks for following up on this.  So the fix I installed avoided the
 > backtrace, but it didn't lead to the behavior you want, i.e. the one
 > promised by `ibuffer-default-shrink-to-minimum-size'.
 >
 >>From reading the code it seems here that the intention is that
 > `ibuffer-default-shrink-to-minimum-size' should only work when
 > `ibuffer-auto-mode' is also enabled?  But that is not documented, is it?
 >
 > Does anyone know how any of this is actually supposed to work?

I suppose the attached would fix it.

martin