It took longer than I expected, but I finally integrated an authentication system into Multy.me!
The idea remains the same, you can anonymously create lists of sites, but if you want to update your lists, you can create a free account.
For the moment the system is in beta, and I hope to integrate a payment system to add a "premium" status. I'm still thinking about features for paying members, the most obvious one for now is the possibility to create custom URLs for your lists.
I also want to create personalized pages per user, a bit like linktree.
Feel free to test this new feature! And especially to report bugs... ;)