my question is in French, Quand je veux enregistrer des mots de passes lorsque je vais pour la premiere fois sur un site,il ne pose pas la question,comment le parametrer pour qu'il pose la questio?

See Password manager - Remember, delete, change and import saved passwords in Firefox

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Good morning,

thank you very much for this answer which resolved problem. 
For mozilla, it would be nice he will have this type of explanation during the changes of version in the French version. 
Still thank you very much.

You're welcome