The easiest way to use the jss extend plugin in your Material-UI application is to use the default JSS plugin presets, which includes jss extend. Material-UI has several JSS plugins installed by default, but jss extend isn't one of them. Let's take a look at the App component in this example to see how this JSS plugin is made available:
const App = ({ children }) => ( <JssProvider jss={jss} generateClassName={createGenerateClassName()} > <MuiThemeProvider theme={createMuiTheme()}> {children} </MuiThemeProvider> </JssProvider>);
The JssProvider component is how JSS is enabled in Material-UI applications. Normally, you wouldn't have to interface with it directly, but this is necessary when adding a new JSS plugin. The jss property ...
