I don't claim that this *should* be the case, but we *might* want to make
the default (i.e. empty input) customize all variables. That would
consistent with what customize-face does.
In any case, users should not see a Customize buffer for nil.
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em
M-x customize-variable RET
Get customize buffer with this:
Nil: Hide Value nil
State: NO CUSTOMIZATION DATA; not intended to be customized.
You need two RETs to get that result. Fortunately I was able
to guess what the test case was.
I will fix it.
Thanks.
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