Comment 90 for bug 572772

I have the same problem with Kubuntu Oneiric. firefox 7.0.1+build1+nobinonly-0ubuntu2, firefox-kde-support 0.6.2-0ubuntu2. The issue can be reproduced as described in comment 83.
Open http://countdown.opensuse.org/11.4/large.png in firefox, right click -> save image as, and nothing happens. If it works (a rare occasion), just try it again, it will fail soon.
browser.download.saveLinkAsFilenameTimeout does not fix it.
If I start firefox from console, the following gets printed:

kmozillahelper(8664): couldn't create slave: "Nem sikerült egy io-alfolyamatot létrehozni:
a klauncher válasza: Ismeretlen protokoll - ''.
"
kmozillahelper(8664): couldn't create slave: "Nem sikerült egy io-alfolyamatot létrehozni:
a klauncher válasza: Ismeretlen protokoll - ''.
"
kmozillahelper(8664): couldn't create slave: "Nem sikerült egy io-alfolyamatot létrehozni:
a klauncher válasza: Ismeretlen protokoll - ''.
"
X Error: BadWindow (invalid Window parameter) 3
  Major opcode: 20 (X_GetProperty)
  Resource id: 0x6400012

Removing firefox-kde-support makes save image as work, but it displays the ugly gnome dialog then.