[tocode] prevent work loss from auto logout

lost my editing posts twice today (2-3 hours of work) due to automatic logout by system - an issue to address later - if workspace is predominantly web-based, losing work this way is unacceptable - simple solutions incl -
> cache inputed material and dump it back into the messagebox after re-login ;
> dialoguebox to warn data loss and default not leaving the edit page ;
> longer default logged-in duration ; user-specified logged-in duration ;