I can find lots of entries in my 404s log ending with /undefined.
The referrer is always the same url of the entry, without /undefined.
URL flagged: http://www.ottimizzazione-pc.it/capire-quali-cartelle-e-file-occupano-piu-spazio-nel-computer/undefined
What does that mean? How should I fix this?
A few more posts with the same questions haven't been answered, such as