16w39b too.
another wrong lighting
Still issue in 16w38a.
Still in 1.10.2
To Henry: It's not on a server and I don't have any command block replacing it. To redstonehelper: I'll try that tomorrow, but it seems to stop behaving like this.
Discovered actual bug. (The older was only a result of this bug.)
It works, silly me.
Oops, didn't realized that the block state is a number. I thought it was the new "facing=..." thing. Can moderator please delete this issue?