This issue may have already been brought up, I'm unsure: I've noticed since the recent patch the quest widget often bugs when accepting/progressing new quests.
For example, see the image below. In this instance my character has just received the quest, however it is already struck-through. This is happening quite a lot of late, seemingly to the first quest in the widget.

Thanks in advance for fixing this issue.

Related: Not sure if this is a new bug, but if there are too few quests to scroll in the quest window, none at all will display (except main quest, and whatever the "recently updated" setting is).

Occasionally, actually.. a lot of the time when you're in a party you can complete a quest but not turn it in (permanently even if you re-accept it) or it does what it does what it is showing on your screen. Curious, were you in a party?