When you go to the quest page and sort by Not Completed. If you don't have some multiple of 30 the numbers at the bottom will be off on the last page.
Right now my page 2 for incomplete quests states
Showing 21-40 of 30
I do have 30 incomplete quests, but it is counting the second page as a full page of incomplete quests and showing 21-40 instead of 21-30. It's not a really big deal.
I've also noticed that when you hover of quests on the game page or the user profile page the Players Completed number will include a comma separator (if more than or equal to 1,000 players have obtained the quest). However the quest page does not include a comma for the Players Completed number, when more than or equal to 1,000.
[ On quest page nineteen thousand looks like 19000 ] [ On game page and user profile page nineteen thousand looks like 19,000 ]
It is indeed a cosmetic flaw, but nontheless... a flaw. I will forward it to the staff and they can fix it when they have time. I'm a big fan of correcting small mistakes and text errors, so a "thumbs up" to you is in place here! Good catch man! =)