consensus and conservation annotation rows are blank for all new windows

Some people who worked through the Jalview tutorial with Jalview 2.6 reported that automatic annotation rows became blank for all newly created alignment windows, regardless of any of the annotation display or calculation settings.

No errors were reported in the console prior to the bug being observed. The only way to restore the conservation and consensus calculation was to save a jalview project and import it into a new Jalview instance.