> An alternative is to have C-h and F1 temporarily show a longer line
> with more commands.
>
>> One idea would be to choose between the short and long messages based on
>> the size of the miniwindow as well as the length regexp and replacement
>> text.
>
> That could also be a possibility.

Between this and your suggestion, I'm undecided what's better.  Perhaps
this is more complicated than necessary.