Rated 5 out of 5 stars
I really liked having Ctrl+Shift+Z for fast page style toggling. So I was disappointed when this didn't get upgraded for Firefox 3. But just now I learned how to get it to work in FF3.
1) install the add-on. A nice guide is at http://www.palaestratraining.com/blog/2008/07/firefox-3-make-older-add-ons-to-work/
But in case the link is down, here's how to do it: You'll notice that the "Add to Firefox" button is grayed out. But below it click on "See All Versions". Now right click on the "Add to Firefox" button for version 1.0.3 and choose "Save link as" to download the .xpi file. This file is basically a zip archive, so use a tool like 7-zip or Winrar to open the xpi archive. You need to modify one variable in the install.rdf file - maxVersion - which is currently set to 2.0.0. Change it to 4.0.0 or higher. Then save the new install.rdf and import the modified xpi into FF3 with File->Open. This will now install the add-on, since the maxVersion is okay with FF.
If everything works fine now, you're done. But the Ctrl+Shift+Z shortcut didn't work for me right away. So I had to do another step:
2) figure out which function is already using Ctrl+Shift+Z and replace it with Read Easily. The way I did it was with another add-on called Keyconfig (located here: http://forums.mozillazine.org/viewtopic.php?t=72994). It allows you to modify all keyboard shortcuts (both built-in FF and add-ons), so I sorted by shortcut and it had the Ctrl+Shift+Z conflict highlighted. Then I disabled the other function and now Read Easily works perfectly, just like it did in FF 1&2.
This was the only thing I missed from FF2 and now I have it again!