Changing Blanks to all using select filtering.

Playability

I'm looking at https://datatables.net/examples/api/multi_filter_select.html and it strikes me it would be more intuitive to have the default selection option to say ALL instead of being blank. How would one achieve that?

mRender

table.column( i ).data().unique().sort().each( function ( d, j ) {
            select.append( '<option value="'+d+'">'+d+'</option>' )

I'm not sure if this would work but it might say ALL:

<option value="'ALL'">'ALL'</option>

Playability

No I couldn't make that work. Mind you the multi filter select example is flawed anyway - once a selection has been made, setting it back to nothing does not restore the full table.