How can I change Firefox's default dictionary?

It's aboot time I asked this one. Firefox thinks I'm Canadian.

I've got absolutely nothing against Canadians and their spelling is a lot better than Americans' but I don't spell specialised with a z. There are other, similar issues where I'm writing something and suddenly the dunce-squiggle pops up.

Anyway... How on earth does one set the default language? Can I remove English (Canada) completely?

Some clarifications as to why some of these answers aren't right for me, but might be right for somebody else:

• Select another dictionary in Firefox by right clicking a textarea — This didn't hold between sessions. I would quit Firefox sipping my cup of tea, start it back up and be halfway through O Canada.

• Remove the Canadian dictionary from Firefox — Simple: I didn't have it installed. The only dictionary language pack I had installed in Firefox is GB.

In my case I had somehow installed system-wide dictionary packages for en_CA and en_ZA. I've still no idea why or even how these kept replacing the Firefox default because I also have a system-wide en_GB dictionary package. Very odd. Package.

Solution 1:

Firefox seems to use myspell/hunspell and listing /usr/share/myspell/dicts/ shows me the dictionaries that I'm given options to use:

$ ls -1 /usr/share/myspell/dicts/*.dic
/usr/share/myspell/dicts/en_CA.dic 
/usr/share/myspell/dicts/en_GB.dic
/usr/share/myspell/dicts/en_ZA.dic
...

Search for the dictionary filename in installed packages:

$ dpkg -S /usr/share/myspell/dicts/en_CA.dic
hunspell-en-ca: /usr/share/myspell/dicts/en_CA.dic

So with the Canadian language package name, the fix is to remove it:

sudo apt-get remove hunspell-en-ca

Solution 2:

Insperatus's comment deserves to be a full answer. I've had this problem not only with Canadian spelling, but sometimes Firefox would use UK or Australian spelling. On Ubuntu Linux, removing the dictionaries from the system for non-US English fixes this problem.

sudo apt-get remove myspell-en-au myspell-en-gb myspell-en-za hunspell-en-ca && sudo apt-get install myspell-en-us

Before:

After:

Solution 3:

A simple answer is saying that a language pack is an Add-on.

• Go to Tools -> Add-ons.
  If you are using Ubuntu 12.04 or newer, you can use Dash to search in your menu; Tap Alt, and start typing Add-ons.

• After you open the Add-ons manager, click on the Languages tab in left menu. There, you can disable any language.

• After adding a language, just right click on any text area, or input field (By default input fields have spell checking disabled, so you will need to enable it before proceeding to the next step.).

• Choose Language from the context menu, and select the language you want, and this will become your default language until you change it again.

P.S. Clicking on "Add language" in the context menu, will take you to a page which contains a listing of language dictionary packs that links to their corresponding add-ons.