Has happened twice to me recently. Where almost all the the navigation related UI does not appear in the star chart, as well as squad related UI when pausing/pressing the ESC key. Both times for me it occurred after finishing a mission as part of a squad of two where I was not the host. The first time the issue was fixed with the host of the squad leaving. The second time the bug occurred, the host left, however the issue remained. After traveling to a relay through the syndicate console the missing UI returned.