Close Firefox blank pages automatically when you download a file
You may find it annoying when you download a program or zipped file that Firefox opens a blank page.
To avoid this and have blank pages opened from download links to be closed automatically, you can use this free Firefox addon called Tab Mix Plus.
After installing Tab Mix Plus open its options and in the first tab (Links) check to activate the option “Prevent blank tabs when downloading files”.
You may even define after what extensions (.zip, .exe, etc.) this option is triggered, but the default list is fine.