Well you awful lot have made me us the horrifying over the last couple of pages so let's try something wholesome again. I actually found out about this last week but got distracted.
As has already been brought up a few times in the thread Mysterious Cities of Gold was a thing that released back in 1982. I'm not going to embed the intro for the dozenth time but it was an okay show with some interesting nuance in its plots for the age range, an okay soundtrack and some genuinely dark shit. It was a French/Japan project and a lot of the work was done by a little place known as Studio Pierrot. They're still going, muddling along with minor projects that most will never have heard of (this is sarcasm).
30 years later it got a sequel series. And yes, it was a sequel. The plot followed on from the original with the same storyline and characters. It was not great but it was good and the fact that someone greenlit a sequel show for people old enough to have children of their own of a similar age to when they watched it was kind of entertaining. The second season was followed by a third a few years later.
And now the 4th is confirmed. According to Wikipedia it premiered on RTS1 which is a television channel in Switzerland specifically targeting the French speakers of the country.