I previous (v4) I used makeStyle to pass class to PopoverClasses property in element.
How to fill this prop in v5 version where makeStyles is obsolete?
PopoverClasses prop from Menu is used to inject the class names to the Popover component, whose classes prop has these CSS properties that can be overridden. You can do the same in MUI v5 by getting the popoverClasses from the Popover and apply to the Popover component like this:
import { popoverClasses } from "@mui/material/Popover";
<Menu
sx={{
[`&.${popoverClasses.root}`]: {
backgroundColor: "gray"
},
[`& .${popoverClasses.paper}`]: {
color: "blue"
}
}}
{...}
>