157 unread, in this case. Clicking the link loads all unread, and breaks the window as shown below.

 

http://i.imgur.com/OhNW1sR.jpg

 

Also tried with

- 8 unread on Round Root - everything was fine

- 76 unread on Asthazar - everything was fine

 

It's possible that the number of announcements isn't what's breaking the window, but one of the announcements itself because of its layout.

 

Suspect: http://magicduel.com/page/Announcement/view/3501 - this ann. was not in the range of unread anns. for Round Root and Asthazar.

That's the result of a "long line"

 

And indeed in that "suspected" announce you can see the guilty part:

 

blooddrop1,jewelshards,osirisbelt,blacktear,claw3,claw1,emeraldglare,purpurfog,purpurmoon,darkshield,blooddrop3,blooddrop2
Dragual Monarth - 9th Anniv age:406 tokens: purpurfog,purpurmoon
Zleiphneir – Ancient Grasan ID 398 age 2850 tokens: blooddrop1,jewelshards,osirisbelt,blacktear,claw3,claw1,emeraldglare,purpurfog,purpurmoon,darkshield,blooddrop3,blooddrop2,blackdiamonds

This has been resolved.