This is a bug in the ubuntulooks theme engine, as identified in bug #135650 (marked as duplicate of this bug). This looks like a bug inherited from an earlier version of the clearlooks theme engine and is fixed in the current version; g_free() is used to free memory that was allocated with a type-specific allocator function, which explains why debugging with G_SLICE=always-malloc isn't too productive.
A short patch to use the per-type free() functions will fix this; patch to follow shortly.
This is a bug in the ubuntulooks theme engine, as identified in bug #135650 (marked as duplicate of this bug). This looks like a bug inherited from an earlier version of the clearlooks theme engine and is fixed in the current version; g_free() is used to free memory that was allocated with a type-specific allocator function, which explains why debugging with G_SLICE= always- malloc isn't too productive.
A short patch to use the per-type free() functions will fix this; patch to follow shortly.