That is an ad. Sometimes using such ads leads to fake contests, ID theft, or even malware.

naescher said

starting it appears a message that i have won a samsung s9 ... What do in this case?

This was from a malvertising Ad on a site you were viewing. This was Not from Mozilla or the Firefox web browser.

This is a scam to try and trick people into giving details like name, address, email, phone# and credit card information to supposedly pay for the cheap $1 shipping.

Mozilla has never had expensive prizes from random websites though they have done some prizes like limited edition t-shirts in a few occasions to say extension developers.

What to do in this case is ignore this scam.

naescher said

starting it appears a message that i have won a samsung s9 mobil telephone - and answer a questionairy and fill up adresse and e-mail and tel number. What do in this case?

I thought firefox can stop that. thank you for your help