As you might have seen from the May 2018 Developer Update, the Extension Manager is getting an update! We’re bringing categories and an updated UI to the Extension Manager, and part of this update will include an additional requirement for extension submissions.
Starting next week (June 4), the developer site dashboard will be updated to support additional requirements for you to fulfill before submitting your extension for review: choosing a category for your extension and providing a new image asset for the Extension Manager.
Read more in the full post over in Announcements found here for how it affects your extension!