Insult about current German domain seen on car (9)
I believe the answer is:
sidelight
'domain seen on car' is the definition.
I can't judge whether this definition defines the answer.
'insult about current german' is the wordplay.
'insult' becomes 'slight' (I've seen this before).
'about' is an insertion indicator.
'current' becomes 'I' (symbol for electric current).
'german' becomes 'de' (abbreviation for Deutschland).
'i'+'de'='ide'
'slight' enclosing 'ide' is 'SIDELIGHT'.
Can you help me to learn more?
(Other definitions for sidelight that I've seen before include "thin illumination" , "Additional or incidental information" , "Car part" , "One shines" , "Visible warning" .)