Thanks for suggestion, Ding!
Actually we've been told about the need to clean and improve our marketplace by many vendors and users during the last several years. And we've been thinking about it during these years. Now it's done.
Many vendors already resubmitted their plugins and started meeting all the new requirements. They also fully supported us
But few vendors don't agree about the requirement to share source code. Actually it's the only requirement that it's being discussed here. And I can ensure that this requirement is final and won't be removed. All vendors have two more weeks to meet new requirements. If some vendor doesn't want to share source code, it's absolutely OK. And we fully understand him and respect his decision. In this case he can always offer extensions on his website without submitting them to our marketplace. In this case there's no need share source code