Focus issue when using WindowsFormsHost within WPF window

Hello,
My application includes a ribbon with a contextual tab, this tab needs focus in order to be activated.
When i open a WPF floating window which hosts a WindowsFormsHost inside of it, my contextual tab isn't receiving focus.
but when i open the same WPF floating window without the WindowsFormsHost my contextual tab does receive focus.
So it seems like WindowsFormsHost "steals" the focus.
Does anyone encountered this problem and knows how to work around this?