Squeeze is on Iceweasel 3.5, which is really old. You would have to install Firefox from the tarball on Mozilla's website, or else compile a newer version of Firefox or Iceweasel yourself.
is there any better solution... something like using backports or things like that?
If i would have the time to compile my own packages i would switch to unstable instead of running the stable branch.
Zotero requires Firefox 3.6 or later—that's it. If you need to run current software and don't want to install/compile things manually, don't run Debian Stable. You're entirely on your own for this.
don't know about Chrome - you'd have to try, but obviously we don't test on years old versions of Chrome. The standalone version isn't packaged for any linux distro currently, but it should just run with ./zotero from the commandline (at least it does in other distros).
I don't really see how downloading & using the offical binaries from mozilla would take "time". But, you can use backports to get a newer version of iceweasel: http://mozilla.debian.net/ I've not tested zotero with iceweasel, though.
I run zotero for firefox on debian stable using the release from the debian mozilla team repository http://mozilla.debian.net/ (now firefox/iceweasel is at 12.0 version) then install zotero plugin.
For me it works perfectly.
Debian stable is a very stable and complete distribution for productivity use. You can always update the software you need to the latest release keeping the system stable.
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If i would have the time to compile my own packages i would switch to unstable instead of running the stable branch.
Ist there a debian stable package for the standalone version?
http://mozilla.debian.net/
I've not tested zotero with iceweasel, though.
For me it works perfectly.
Debian stable is a very stable and complete distribution for productivity use. You can always update the software you need to the latest release keeping the system stable.