bug#29279: Sharing the margins

[martin rudalics]

> This would make it hard to request to be the leftmost or rightmost
> column, I think.

most-negative/positive-fixnum maybe?

>> BTW is ‘window-margin-modify’ just for the sake of the line numbers
>> codes or which other users would it have?
>
> Any package whose requirement of the margin width is not constant, but
> has to change due to some event.  Even visual-fill-column should need
> it, I think.

What is visual-fill-column?

martin