Ikony MUI Wolna kompilacja
//instead of
import {
AppBar,
Button,
Hidden,
IconButton,
Toolbar,
} from '@material-ui/core';
import { Menu } from '@material-ui/icons';
//Do this:
import AppBar from '@material-ui/core/AppBar';
import Button from '@material-ui/core/Button';
import Hidden from '@material-ui/core/Hidden';
import IconButton from '@material-ui/core/IconButton';
import Toolbar from '@material-ui/core/Toolbar';
import Menu from '@material-ui/icons/Menu';
CyberCat