Change langage of "List of Figures" and "Chapter"

PB25

I am finishing a relative long academic document by using a project (documentclass: book). This doc is in French. I indicated lang : fr-FRin YAML. Everything is almost perfect in PDF output, except for 'List of Figures' and 'Chapter' 1, 2... I would use the French word but I can't find an appropriate solution.
For instance, lof-title: Liste des figures doesn't work.

Any idea ?
Thank you in advance

My current YAML :
`documentclass: book
pagestyle : plain
standalone : true

author:

XXX (XXX)

lang : fr-FR

subtitle:
- YYYY
date: BBBBB
toc: true
toc-title: Sommaire
toc-depth: 4 #
numbersections: true
section-divs: true
margin-left: 2.2cm
margin-right: 2.2cm
margin-top: 2cm
margin-bottom: 2cm
lof: true # liste figures
lof-title: Liste des figures
link-citations: true
reference-section-title: Bibliographie
urlcolor: blue
dpi: 200`

hendrik

Maybe the defaults files defines English terms for that already? Defaults files often override YAML frontmatter values, so this could be one reason.