How to scoll the second popup menu like file content preview

[Pger-Y]

Sorry for bothering,I search scroll in discussions by can't find the same question,so i made a new one,home i haven't miss any thing :( Here is my lunarvim config,I follow the doc to set the C-b and C-f

but still can't scroll the file preview menu,unless set mouse on then i can scroll by mouse,is there any mistake in my conf T-T