On recently upgraded machines (Jaunty->Karmic) and newly installed Karmic machines (they come with FireFox 3.5.4 I believe) I am noticing this "Ubuntu Firefox Modifications" add-on. What exactly is this add-on? What does it do? Are there any bad effects of disabling it? And finally, how to purge this from the system.


5 Answers 5


In this post on an Ubuntu forum thread someone poked around the package contents to see what the addon's source actually does when enabled. It lists the following functions:

  1. Enables usage of Ubuntu plugin finder service.
  2. Allows localization of extension descriptions.
  3. Sets several browser defaults, like printing, look-and-feel, disables checking for default browser, locale matching with OS, etc.
  4. Adds Ask.com search plugin.

One undesirable side effect is that it seems to interact oddly with a number of other extensions1 such that you can not add their toolbar buttons to any toolbars, even on the default theme2. Disabling the Ubuntu extension re-enables adding these buttons to toolbars.

1. most notably FlashBlock and TabMixPlus in my case
2. some people suggest the problem is related to theme choice, I have found this not to be the case


It allows you to install Firefox add-ons through the Ubuntu package manager. If you disable it, you won't be able to install add-ons through the package manager. You should be able to remove it as normal, but I'd recommend just disabling it at most.

  • Do you mean that it allows me to install FF addons as if I were installing Debs of those addon? So, if I were to install an addon, it would it get installed globally due to that extension? Sorry, I am still not clear about it. If it is the former case, I think the extension would not work for non-admin users.
    – user16354
    Commented Nov 3, 2009 at 17:10
  • It allows you to install it for your user account.
    – user1931
    Commented Nov 3, 2009 at 17:17
  • hmm ... okay. So if it allows me to install an addon for my own user account, what is the Ubunut Modifications addon's advantage over the usual method of installing addons (by clicking on xpi files or download them and installing)? Sorry for further questions, but am still not clear on what extra role the addon plays for a typical user.
    – user16354
    Commented Nov 3, 2009 at 18:10
  • You can search in the package manager instead of going on the internet and searching the mozilla add-on website.
    – user1931
    Commented Nov 3, 2009 at 19:07
  • Yes, that is one way, but I didn't know the name of the specific package. Well, going on the internet and searching gave me this: packages.ubuntu.com/karmic/ubufox. But that description does not shed any insightful light on this.
    – user16354
    Commented Nov 3, 2009 at 19:34

That extension has been part of Ubuntu's Firefox for a while, or so I thought. I've seen it as early as intrepid. As others have said, it's simply to allow extensions to come in through the Ubuntu repos.

Disabling it will have no ill effects on your system.

To remove it, remove the ubufox package.


Disabling it also brings back the "middle click paste to go to website in pastebuffer" function. I missed it enormously.


Disabling it also brings back the ability to drag URL links to your desktop. A feature I missed so much it almost made me switch to a different default browser.

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