In firefox, I receive the error message "<file>,could not be saved, because you cannot change the contents of that folder." every time I try to save to a folder outside the default firefox downloads folder. I receive this message even if I am owner of the folder and I explicitly have write permissions to that folder. I've even tried setting permissions 0777 with no luck. I have the issue every time I right click on anything (a link, an image, a file) and try to "Save image as.." etc.

This has been happening since the firefox included with Ubuntu 10.04 LTS. I have gotten around it in the past by downloading firefox directly and running it on my own (/usr/local/firefox/). However I would like to try and resolve the issue now that I've upgraded to Ubuntu 12.04 LTS. The issue only exists with the firefox installation included with Ubuntu. It does not happen with chrome.

Any help is most appreciated.