Crash opening "settings" dialog when a non-existent database is selected.

Continuing the ~~#110~~ report, on one of the non-existent databases, if i try to open Settings by clicking on the button in the ribbon, an exception occurs (see attached log). Also, Cleanup and Miss/Have produced the same exception.

Not an actual issue on a properly loaded database, but you may want to take a look at it. Perhaps if the selected database does not exist, all buttons and tasks in menus should be disabled.