kepp User

On the line 85:
Original:
var filename = filedetails.title + ' (' + publishedfileid + ').json';
Greasemonkey on Firefox 43.0.3 was complaining about unknown publishedfileid variable.
Changing it to following fixed it for me:
var filename = filedetails.title + ' (' + filedetails.publishedfileid + ').json';

Thanks for great script :)