Version: (using Devel) Installed from: Compiled sources OS: Linux As explained in more detail in #159047 the "Defaults" button doesn't work as expected: [...] Appearance -> Theme Manager NO [2] [2] seems to do "something": There is no Theme entry for the default Oxygen. Selecting a theme, then Defaults runs "Updating system configuration", but doesn't actually change anything. [...]
*** This bug has been marked as a duplicate of bug 159047 ***