[Gahera]

Have found an actual work around. Tested and confirmed, useful until the issue is resolved.

As mentioned by TristanDamian, untick box for "Use Alt-L instead of L for Carbonite Quests"

From my testing in the past couple of days, this has worked some times and other times it didn't do anything. However, I found an extra work around which has worked every time so far.

When you have am NPC quest frame open and you see that the text extend beyond the frame, simply hit "L" which should close your current frame and open the Blizzard Quest Log. Close quest log, talk to NPC and the text should be normal now.

Edit: I would like to add that the action I have described in this post seems to be a refresh of sort. I am using Pawn which shows an icon on the quest reward item that is worth the most. Sometimes the icon wouldn't show for some reasons. I noticed just now that my work around also fixes that.