I recently found a ridiculous edge case that no test case caught and is very hard to debug and fix.
Then, I was assigned to find and fix it.
FML

Next time keep your mouth shut :D

“Date is invalid for five digit years.”
“Shut up Carl.”

Update test cases to find edge case

Actually happened to me too this week. I wonder how qa and testers methodology may help (@Floydian gonna tag you here but actually interested in your answer, not as part of the competition. So if you want I will not count this one. Though [hubiruchi-6 @Floydian-0])