No.
But I know that when you first sign in, there is a check box, that you can tick, to keep me signed in, which I think last for up to 24 hours unless you want to sell etc, (in which case) you have to sign in again.
I wish someone did know the answer because mine is just the same and has been for more than a month,
I can,t even move between pages without signing in each time or when browsing lists to "watch" items I have to sign in for each item I want to watch and I can,t delete an item from any list without signing in for each item I need to delete,
but I can get on from my emails without signing in each time so I am puzzled