Every time Firefox updates their browser version, it’s the same story: the delicious extension is said not to be compatible. It looks like the new delicious owners are quite slow on the uptake…
But fortunately there is a decently simple workaround that works. The problem is not that the extension is not compatible, but it is not declared to be so. Simply modify the description file for the extension, tell it that you Firefox version is fine, and try it out. It has always worked for me so far.
Under Linux, locate your Firefox profile. In my case it is called zm84ac6z.default. Within this you will find an extensions folder:
$ cd ~/.mozilla/firefox/zm84ac6z.default/extensions
There you will find several subfolders, each named with some UUID, a hex string that looks sort of {2fa4ed95-0317-4c6a-a74c-5f3e3912c1f9}.
Locate the one for the delicious extension. In my case it is the one above, but you can always locate it:
$ find -name install.rdf -print -exec grep delicious.com {} \;
Once you’ve found the proper install.rdf file, edit it and look for something like em:maxVersion="4.1". Replace this with something like em:maxVersion="6.*" and you should be good to go for a while… It’s working fine for me on Firefox 5.0 on Ubuntu.
Good luck!
BTW: the process in Windows is similar, only the folder names are different…
Thanks to my colleague Marc Sallés for the tip!
techno milk 