Window freezes after Lich King battle win

Hi there,

I killed for the first time the lich king yesterday with my priest.
I got the image with Anduin becoming the new Lich King but after I click next the window freezes and impossible to do anything else after that >_< ( forced to hard quit )

I thought I may be a bug with my pc at the time but I’ve just killed LK with my warrior => same thing

Plus, a detail but, when the first animation plays with " There always must be… " " … a Lich King" => the new image of the corrupted hero does not appear for some reason.

My config : PC ( Windows client )

Best regards,

Asunro