The "Requests" module in the menu bar displays a counter.
It counts all the requests in statuses with the "Include in header count?" configuration enabled.
Follow these steps to configure the statuses to include in the header count:
Step 1: Go to "Administration" > "Request statuses".
This loads the list of status.
Step 2: Click the Edit button of a given request status.
This loads the "Update request status" form.
Step 3: Enable/Disable the "Include in menu header count?" configuration accordingly.
Step 4: Click the "Save" button.