Custom ui through frontend.yaml still necessary?

Installation Home Assistant OS
1

HI,

Searching for custom ui issues, I stumble on this setting, which I cant find documented anywhere to be necessary loading the custom ui.

frontend.yaml contains:

javascript_version: auto
extra_html_url:
    - /local/custom_ui/state-card-custom-ui.html

    - /local/custom_ui/state-card-value_only.html
    - /local/custom_ui/state-card-tiles.html
    - /local/custom_ui/state-card-table.html

extra_html_url_es5:
    - /local/custom_ui/state-card-custom-ui-es5.html
    - /local/custom_ui/state-card-tiles.html
    - /local/custom_ui/state-card-value_only.html

themes: !include frontend_themes.yaml

Ive installed Custom Ui according to https://github.com/andrey-git/home-assistant-custom-ui/blob/master/docs/installing.md#automatic-install which doesn’t mention this at all.

Is this still necessary??

Cheers,
Marius