Improve "All extensions" button from Extension Manager

During an usability testing session, an user wrote in the "Search" bar the extensions she was looking for (calendar) and after, instead of pressing the Search button or Enter, she pressed the "All Extensions" button. 

The result instead of being "Calendar Application (Pro)" (or any other calendar extension we have), was "Google Apps Integration (Pro)". The user concluded that we don't have "Calendar" extensions. 

The issue is about the proximity and position of the "All Extensions" button, that can cause confusion.

I propose to replace the "All Extensions" button with a tab, see images.