who is downvoting me and why?

You’re probably making them feel stupid, people downvote for no good reason. It’s a them problem, not a you one; everybody should check AlternativeTo before asking for recommendations.

I had no idea this had a self-hosted platform category. Cool!

Sorry, I thought I already replied but seems like I didn’t: thank you for such cool link, I didn’t know we could filter there by hosting criteria. Unluckily, none of them is good enough as Genially. The closest one I found is Penpot, but is more focused on landscape designs as it is on slides. This is the kind of software that I’m looking for but for self-hosting.

Hi! Sorry, I thought I already replied but seems like I didn’t. While Slidesk is very cool, it’s more like a Prezi alternative as it is for Genially. They are very different slide programs :( Genially is more like a slide program that can be more similar to Canva, but with interactive buttons and effects. Here’s a short view of what it does