Hi, it does not show them as installed here but does not mean much.

Are you going to the 3 Bar Menu --> Options --> Languages --> Choose then moving it up or down ? Have you restated Firefox since installed ? Have you gone to add-ons to make sure they are installed ?

Note: Mcafee can present issues sometimes.

mike_nl said

I tried to install two lanuage packs to use them in webmail

I take it you want to add languages for the Spellchecker and not change the user interface or UI of Firefox?.

from https://addons.mozilla.org/firefox/language-tools/

Installing a dictionary add-on will add a new language option to your Firefox spell-checker, which checks your spelling when you fill out Web forms. Language pack add-ons change the language of the entire application.

https://support.mozilla.org/en-US/kb/how-do-i-use-firefox-spell-checker#w_adding-dictionaries

What language packs are used for: https://support.mozilla.org/en-US/kb/use-firefox-interface-other-languages-language-pack

Language packs are installed properly (see attachment) tried to delete an re-install but that did not help

also made a screenshot where i expect the languages to be visible

I do have Mcafee, can you tell me what the issues are or should i contact them?

Based on your first image you need install Dictionaries and not language packs.

While there is a British English dictionary https://addons.mozilla.org/firefox/addon/british-english-dictionary-2/ there does not appear to be a German dictionary listed on https://addons.mozilla.org/firefox/language-tools/

Hmm perhaps because there are multiple dictionaries to choose from https://addons.mozilla.org/firefox/search/?q=German+dictionary&appver=&platform=

Thanx james for solving this issue

stupid me ;-)