Any way for ff to save files to separate temp directory instead of desktop?

I'm not talking about files I want to download and save to desktop, documents, etc.

I mean just viewing, say a pdf, with the 'open with'. In windows, it would still have to download but it would be in a temp file that is hidden away, while on my mbp it dumps it to the desktop.

It gets even worse when I view the same document a couple of different times, I end up having doc, doc-1, doc-2, etc on my desktop creating a mess.

Any way to get ff to dump to a separate directory for temp files instead of the desktop. I understand safari can open pdfs in the browser and have no need for a download like preview does.

What options do I have? Safari just doesn't have the functionality that firefox can with its plugins and extensions.

 

Seems to me thats for files I select download. Mine has it set, ask me where to save files when downloading.

When you click 'open', it still dumps to desktop before opening.

Though I think I just found a plugin for ff that lets it open in the browser (thus bypassing the need to download to the desktop for preview - it still downloads, but to a temp file).

Plugin is called 'PDF download' and seems to be working so far.