It’s not a colourful story? (5,3)
I believe the answer is:
white lie
'story?' is the definition.
(thesaurus)
'it's not a colourful' is the wordplay.
I cannot quite see how this works, but
'it's' could be 'it' (I've seen this in other clues) and 'it' is located in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for white lie that I've seen before include "Justifiable deception" , "Minor falsehood" , "Well-meant falsehood" , "pardonable offence" , "Supposedly helpful untruth" .)