Delete N numbers no longer used

How can one delete the N numbers on the drop down menu that are no longer useful?

Which drop down menu are you refering to?

Top left box for entering flight # or N #. After you enter N, a menu drops down revealing all the aircraft N#s that you have previously entered/tracked.

That’s probably a function of your browser, not the site. I don’t have a drop sown box there myself.

Highlight the N number and push the delete key to remove autoentries. I am assuming you are working off a Windows based computer.

Allen