I found odd bug. Using any portal or Hearthstone when Talents and Spellbook window is open locks Escape button. It stops working. To fix that I need to press Game Menu (question mark) using the mouse.
To reproduce it - open Spellbook and keep it open, don’t close it - now use any portal or Hearthstone. After press Escape, it’s not going to work.
Thought I was crazy so I’ve never mentioned it before but it consistently happens to me after hearthstoning out of the druid dreamwalk zone.
happens to me too. thought my pc was gevok
Hi there Ansui,
Thanks for the report and well done narrowing down the cause, which I imagine would have been pretty tricky to nail down otherwise! 
Looks it’s been reported in-game as well, and hopefully can get fixed soon enough to avoid some unnecessary head scratching – thanks again!