Locale/language issue with Quarto website :/

I encountered an encoding problem on some pages where there were accented characters. For example, using RefManageR package to print a bibliography, my PhD thesis title was rendered as:

"Strat<U+00E9>gies de commande r<U+00E9>f<U+00E9>renc<U+00E9>es multi-capteurs et gestion de la perte du signal visuel pour la navigation d'un robot mobile"

This issue is related to R(studio) being used with a locale that is not compatible with Unicode encoding (e.g. UTF-8). To overcome this, one can simply use the following inside its Rscript:

Sys.setlocale(category = "LC_ALL", locale="en_US.UTF-8")

Next, in some other pages, when I directly write some text with accented characters I would have weird output. Fo example, if I write my PhD thesis title, I will get:

"Stratgies de commande rfrences multi-capteurs et gestion de la perte du signal visuel pour la navigation d'un robot mobile"

This issue seems more related to Quarto. Surprisingly, this troubleshooting doesn’t happen on all pages where there are accented characters 😦.
After some few investigation, ir seems that this will occur when your system locale does not use UTF-8 encoding, such as

foo@bar:~$ echo $LANG
C
foo@bar:~$ locale
LANG=C
LC_CTYPE="C"
LC_NUMERIC="C"
LC_TIME="C"
...

By changing your locale to one that support UTF-8 encoding, the above issue is solved:

foo@bar:~$ export LANG="en.UTF-8"

If you use systemd, it is better use the localectl command.

A last point, it is quite easy to change the locale of your computer and then to publish your website for instance on Github Pages, Quarto Pub or even you own web-hoster. But, if you need the hoster to build and publish on its own server, you have to be aware of the server locale!
If you use GitHub Action, I found the following trick to change the locale on GitHub server:

on:
  workflow_dispatch:
  push:
    branches: main
name: Dfolio deploy
env:
  LANG: "en_US.UTF-8"
  LANGUAGE: "en_US:en"
  LC_ALL: "en_US.UTF-8"
jobs:
  build-deploy:
    runs-on: ubuntu-latest
    steps:
      - name: Check out repository
        uses: actions/checkout@v3
      - name: Set locale
        run: |
         sudo locale-gen  ${{ env.LANG }}
         sudo update-locale LANG=${{ env.LANG }}
      - name: Set up Quarto
        uses: quarto-dev/quarto-actions/setup@v2
        ...

This trick is inspired from this issue