input: [URI] 1 [FURI] 0 [3] 
output: FALSE: When the URI is present but no FURI we return FALSE. Maybe the parent id is wrong (meaning it also has no parent with a FURI) or the icon data is missing: no favicon is found on the page afterwards and no default one is given. Which means: on the next trigger another call to this site is done to try again over and over again. So at a certain moment you would want to say that this site is “frozen” for a month but… that requires a write to the database with no actual favicon uri.