Full Idea
There are many statements which are plausibly viewed as conceptual truths (such as 'what is yellow is extended') which do not qualify as analytic under Frege's definition (as provable using only logical laws and definitions).
Gist of Idea
Many conceptual truths ('yellow is extended') are not analytic, as derived from logic and definitions
Source
B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], 3.2)
Book Reference
Hale,B/Wright,C: 'The Reason's Proper Study' [OUP 2003], p.12
A Reaction
Presumably this is because the early assumptions of Frege were mathematical and logical, and he was trying to get away from Kant. That yellow is extended is a truth for non-linguistic beings.