40.6
====
* Fix sound-file support in notifications [Florian; !1991]
* Fix high-contrast switches [Florian; !2000]
* Only allow one extension prefs dialog at a time [Florian; #4564]
* Fixed crash [Sebastian; !2014]
* Misc. bug fixes and cleanups [Florian; !1998, !2007]

Contributors:
  Sebastian Keller, Florian Müllner

Translators:
  Yuri Chornoivan [uk], Matej Urbančič [sl], Anders Jonsson [sv],
  Rafael Fontenelle [pt_BR], Kukuh Syafaat [id], Hugo Carvalho [pt],
  Christian Kirbach [de]