From: Thomas Frössman <[email-masked]>
Date: Fri, 8 Apr 2016 19:56:16 +0200

I mixed up the mark/region functions a bit while testing so maybe it's not
an emacs bug. I will continue to investigate later.

My actual problem is resolved by deactivating cua-mode and this did not
happen in emacs 24.x..

The NEWS file says that "deactivate-mark is now buffer local".. that could
maybe be related.

-- 
Thomas Frössman
http://t.jossystem.se