Forum Academy Marketplace Showcase Pricing Features

What is the maximum number of collaborators who you can work with in one app?

I’m a bit confused about what bubble means by collaborators.

It says here it’s up to 40: Features | Bubble

But reading the pricing page, it says one app editor on the free/starter plan, so does the editor count as a collaborator? And if you do invite someone to collaborate, are you going to get charged? Like if I wanted to invite 50+ collaborators, I have to pay for each of their seat?