Drop files into attachment boxes instead of browse for them or type in the filename. Drop multiple files and fill all the entries. In some websites it allows to add new upload files: in Google Mail is possible to drop the files directly over the "Attach a file" link.

A Sidebar allows to drop files from a listing

It is now possible to drop text snippets and the extension generates a temporary text file. This is useful with Thunderbird allowing to drop text from an email as a new .eml file.