Accidentally added an item to momento and singleton list; How do I remove it?

[lykzomg]

I tried editing the itemflags.txt and removing the item but it keeps returning to the aforementioned list. What should I do?

 

[Bale]

Highlight the item in the memento list and singleton list and press the delete button to remove it. I know that isn't nearly as obvious as it sounds since every other place in the UI has a button or a right-click menu.

 

[lykzomg]

Ahhh
Thank you very much! My OCD side thanks you greatly.