I have tried on about 3 occasions to change the default language of Firefox from US to UK English. It has never stuck, so the spelling corrections I make when marking student's work are shown as errors.
How can I ensure that the language setting NEVER reverts to US spelling?

Het pakket vult mooi aan wat ik even ben vergeten ...

It is not clear that this package is not for spellchecking

does not work ; english does not appear in the choice of languages for correcting the text

My Great Britain.

Je souhaite harmonisée mon anglais,merci.

It's so nice to not have Firefox telling me to spell words ending in ....ise as .....ize or spelling colour without the 'u'. Now to find out how to make it my default.

Boa

Not possible to install it, cause you *have to update your browser*. But in fact, when you have already updated it, you still got nothing.

Tried to add the English (English - UK) dictionary, I got a message stating that I needed the latest version of Firefox to install it, so I downloaded the latest version, double clicked to run it, it installed, but it still won't let me install the English dictionary. I would have liked to give it zero stars because it doesn't work.

Easy to use, complete

une langue universelle

Une fois installé, la langue n'est pas proposée. ne fonctionne donc pas (version Version 59.0.2)

Can't select dictionary once it's installed

The language is not changing in Mozilla Firefox even though I keep trying to do so.

Il ne fonctionne absolument pas dans la fonction orthographe. Il est nul