Default [Q] mail widget not refreshing until new email since kitkat update

Hi,

I have, as obvious, a Nexus 7 2013.

it's strange. The email widget shows the last updated email, even though i deleted them.

I see them as fresh new (in bold), until some new emails come in. Even though I delete all the new emails, the widget still shows them and it shows them as new. As new emails come in, the widget refresh, the old deleted email disappear, if they have not been deleted, they are no more shown in bold.

This behavior occurs from the update to kitkat. Before the OTA, all was fine.

Any ideas?

Thanks

Giorgio