Undefined index: map in multipage_jumplist_block_view()

I've the following notice when having 'Non Javascript Multistep' enabled (but not Ajaxify):

Notice: Undefined index: map in multipage_jumplist_block_view() (line 265 of sites/all/modules/contrib/multipage_jumplist/multipage_jumplist.module).

Affected code:

  $js_options['map'] = $jumplist['map'];