This issue is exactly the same I've posted for bitbucket's old design (
#4725) so I will repost it for the new one.
When I open a page of my project on bitbucket.org I see a top menu related to this one. It has an item "Issues (count)" that refers to page with a list of currently open issues (with "new" or "open" statuses).
Working for relatively long time on my project I mentioned that the count of open issues in menu item is not equal to the count of issues in page's title (that is just above issues' list and represents a valid value). To be more precise, the count of open issues in menu item is less than the count in page's title by one. E.g, when count of open issues is 14 I see "Issues (13)" in menu item.
I'm not sure whether such behavior correct or wrong but probably there can be page's caching issue.
A problem becomes apparent on my private repo's page: https://bitbucket.org/Arrenda/arrenda.ru/issues?status=new&status=open