bug#12638: 24.2.50; FR: Some suggestions for icomplete-mode

[Jambunathan K]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> We can also have:
>>     1. an empty space with some background fontification
>>     2. a non-breaking space
>> Both (1) and (2) without surrounding `()'.
>
> An empty space is actually not a bad idea.  I also considered
> a checkmark ✓, but a space is simple and works everywhere.

OK, let's go with `()'.  If we need filler characters let us sneak a
full-stop or a dot operator in between.