Start todays emacs with -Q and set scroll-conservatively to some
    non-zero number, say 1.
    Then type eg. M-x  ABC. Now the minibuffer shows "M-x ABC" as expected.
    But if you type the Danish character A-ring (a capital A with a ring
    above) everything seems to disappear from the minibuffer.

I tried this under X, using the Emacs input method Latin-1-Postfix to
insert the Å, and the failure happened.  What occurred was that the
minibuffer contents all scrolled off the top of the window.

I think the reason for this is that the Å character is taller than
ordinary letters; taller, in fact, than the height of the window.
I think this confuses scrolling calculations so that they believe
that character doesn't fit on the screen while allowing point
to be visible.

Kim, could you investigate this and fix it?