Not a Bug Forfeited quests not deleting

Description of the bug: After forfeiting a quest that won't disappear, it turns grey and is inactive, but remains in the 'In Progress' list:


What is supposed to happen?: Once a quest is forfeited, it should be removed from the list.
Where did you find and/or notice this bug?: I've noticed this sometime last year, actually. I've only just recently picked up quests again, so I'm a bit surprised to see it hasn't been changed.
A step-by-step guide to re-producing this bug (optional): Open up 'Quests', click on a quest under 'In Progress', press the red 'Forfeit' button, shown to be turned grey below the cursor in the screencap above.
Extra information (optional): Note that some quests disappear, as they should, but not all.