While working on the initial changes earlier this evening, I didn't check whether authentication was actually required, because the video ID schemas were still broken. They were showing a football match at the time on the france-2 channel, so I don't know if authentication is required only for certain kinds of content.
I have a second commit that's not part of this PR branch that adds support for authentication (just noticed that it's not working 100% correctly before opening this PR, irrelevant though). If it turns out that authentication is indeed required - and I still don't know - then this will be fixed in another PR.
As you can see, no authentication required, at least right now (using a French proxy - socks5 over SSH):
$ HTTPS_PROXY=socks5://localhost:1920 ./script/test-plugin-urls.py pluzz
:: https://france3-regions.francetvinfo.fr/bourgogne-franche-comte/direct/franche-comte
:: 144p, 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://la1ere.francetvinfo.fr/info-en-continu-24-24
:: 144p, 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://la1ere.francetvinfo.fr/programme-video/france-3_outremer-ledoc/diffusion/2958951-polynesie-les-sages-de-l-ocean.html
:: 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://www.france.tv/france-2/direct.html
:: 144p, 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://www.france.tv/france-2/journal-20h00/141003-edition-du-lundi-8-mai-2017.html
:: 144p, 180p, 288p, 396p, 576p, worst, best
:: https://www.france.tv/france-3/direct.html
:: 144p, 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://www.france.tv/france-4/direct.html
:: 144p, 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://www.france.tv/france-5/direct.html
:: 144p, 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://www.france.tv/franceinfo/direct.html
:: 144p, 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://www.francetvinfo.fr/en-direct/tv.html
:: 144p, 216p, 360p, 540p, 720p, 1080p, worst, best
:: https://www.francetvinfo.fr/meteo/orages/inondations-dans-le-gard-plus-de-deux-mois-de-pluie-en-quelques-heures-des-degats-mais-pas-de-victime_4771265.html
:: 216p, 360p, 540p, 720p, worst, best