My windows manager is Xfce. Using Thunar - when I opened a directory containing perl programs, somethimes I click two times on a perl program to start it. No Xterm appears - what I think that happen is that my disk become full. I happen a lot of times in Wheezy, but in Jessie it happened one times. I don't know if this happens (the disk became full) as I described, if it is a bug of Xfce, or if it is a bug of Jessie. In Jessie I freed some space on disk, and I restat my computer, and everything runs as normal (with space freed). I Wheezy I had a lot of problems.
Sorry for the late reply ! Is it still an issue ? If yes, what is the output of "df -h" .. just to make sure that your full disc causes the problem.
Since there is no further information, I will close the bug for now. Please feel free to reopen if it is still an issue for you !