1436141 - Make it easier to switch language

Status: RESOLVED DUPLICATE of bug 1425941

(Firefox :: Settings UI, enhancement)

Description

[scootergrisen]

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Firefox/52.0
Build ID: 20180118122319

Steps to reproduce:

I would like it to be easier to change language in Firefox.

One way is to download a language pack and change about:config?filter=general.useragent.locale to a language/country code and restart Firefox.

But that only works if you know the exact value for general.useragent.locale.
If i download "Svenska (SE) Language Pack" in add-ons i might think the value should be "se". But no that does not change the language after restarting Firefox.
I have to use "sv-SE". But how would the user know it? The language pack does not seem to provide this info.

If i search for "swedish Language Pack" i dont see the language pack because its "Svenska Language Pack"

The language packs are not using the same style of name.
Like "Svenska" in "Svenska (SE) Language Pack" is swedish.
But "Russian" in "Russian (RU) Language Pack" is english.
And add-ons like "Français Language Pack" don't have a county code "(XX)".
And there is "Español (México) Language Pack" with "(México)" instead of language code.

I would be nice if the user could make a language pack active under add-ons and then the general.useragent.locale setting would be changed without the user having to go to about:config.
And the "Restart now" link would appear when the user changed to another language just like when deactiving some of the add.ons.