post-Xesht, impossible to leave the area

After the fight with Xesht for the first time, after all the loot has been dropped, portal to hideout doesn't react to clicking.
Logging out didn't work.
Restarting the game didn't work.

Leaving the arena itself and entering it again makes Xesht repeat the last dialogue he says when he's defeated.

Character fully stuck in the area. No way to get out.