minibuffer resizes while typing into minibuffer

Question

There is an annoying quirk of my minibuffer. Can you help me trace its origin?

Typing into the minibuffer causes it to instantaneously resize to 2 or 3 lines in height, and then back to 1 line. It happens far too quickly to take a screenshot. Best guess is it is a side effect of minibuffer autocompletion.

Do minor modes in other buffers, like Yas and AC, apply to the minibuffer? I thought not.

Thanks for your time!

Answer 1

Set resize-mini-windows to nil:

(setq resize-mini-windows nil)

You can also customize option max-mini-window-height, to let it resize but limit how much it grows.

See the Emacs manual, node Minibuffer Edit.