Segfaults when looking up supported formats in the GUI
Start mat-gui 0.6, Help → Information → I get a "Supported formats" dialog. There's a "Fileformat" (sic?) drop-down list, with no current default value. If I open that list I see the list of integers from 0 to 11. If I click, say, "4", mat-gui segfaults.
(Off-topic: it seems that the "Supported formats" dialog is not properly associated to its parent -- GNOME Shell doesn't do the same tricks it does for other software that have such dialog windows.)