I'm not sure if I'm doing something wrong, or if new Gerrit UI doesn't support custom dashboards.
I've created a custom dashboard that I really like. It works fine on old UI, but I don't like that UI. It doesn't work at new UI, and I like that UI.
In the old UI, the dashboard opens fine. In the new UI, instead of opening the dashboard, I've redirected to https://gerrit.wikimedia.org/r/dashboard/self.