sort_columns_at_startup not working?

Hi All,

Just found the tweak for sorting book table at startup using the sort_columns_at_startup setting.

However, I copy the example : [('authors',0),('title',0)]
apply the tweak and restart the program.

I then see the table isn't sorted how I want.

I check the tweak and it is now :

sort_columns_at_startup = [['authors', 0], ['title', 0]]

Ideally I want :

sort_columns_at_startup = [('title', 0), ('series', 0), ('authors', 0)]

but I can't get that to work either as when the program restarts, having applied the tweak, I get :

sort_columns_at_startup = [['title', 0], ['series', 0], ['authors', 0]]

and the only column that appears sorted is the titles.

Please tell me I'm doing something wrong, otherwise I'm going mad.

Thanks All