How to install Firefox 4 on Kubuntu 10.10

I’m a Kubuntu 10.10 user who want to use Firefox 4. Here’s what I did

Add the Firefox Stable PPA to the system source

sudo add-apt-repository ppa:mozillateam/firefox-stable
sudo apt-get install firefox

Remove the Ubuntu modification add-on

sudo apt-get purge ubufox xul-ext-ubufox

Remove the old Firefox 3.6 language pack

sudo rm -rf /usr/lib/firefox-addons/extensions/langpack-en*

Done. Now you have Firefox 4 on your Kubuntu.