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Deepen the four format guides and shrink the shared About block #309

Job	Run time
suite (mobile, journeys)	2s
suite (desktop, pages)	2s
suite (mobile, pages)	2s
suite (desktop, journeys)	3s
explore (${{ matrix.leg.persona }}, ${{ matrix.leg.target }})	-1s
plan-explore	-1s
	7s