sets up Window min/max to use correct icons

src/components/WindowTopBar.js

@@ -3,14 +3,14 @@ import PropTypes from 'prop-types';
 import Typography from '@material-ui/core/Typography';
 import MenuIcon from '@material-ui/icons/MenuSharp';
 import CloseIcon from '@material-ui/icons/CloseSharp';
-import FullscreenIcon from '@material-ui/icons/FullscreenSharp';
-import FullscreenExitIcon from '@material-ui/icons/FullscreenExitSharp';
 import Toolbar from '@material-ui/core/Toolbar';
 import AppBar from '@material-ui/core/AppBar';
 import classNames from 'classnames';
 import WindowTopMenuButton from '../containers/WindowTopMenuButton';
 import WindowTopBarButtons from '../containers/WindowTopBarButtons';
 import MiradorMenuButton from '../containers/MiradorMenuButton';
+import WindowMaxIcon from './icons/WindowMaxIcon';
+import WindowMinIcon from './icons/WindowMinIcon';
 import ns from '../config/css-ns';
 
 
@@ -49,7 +49,7 @@ export class WindowTopBar extends Component {
               color="inherit"
               onClick={(maximized ? minimizeWindow : maximizeWindow)}
             >
-              {(maximized ? <FullscreenExitIcon /> : <FullscreenIcon />)}
+              {(maximized ? <WindowMinIcon /> : <WindowMaxIcon />)}
             </MiradorMenuButton>
           )}
           {allowClose && (

src/components/icons/WindowMaxIcon.js

+import React from 'react';
+import SvgIcon from '@material-ui/core/SvgIcon';
+
+/**
+ * WindowMaxIcon ~
+*/
+export default function WindowMaxIcon(props) {
+  return (
+    <SvgIcon {...props}>
+      <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24">
+        <path d="M7,14H5v5h5V17H7Zm7-9V7h3v3h2V5Z" />
+        <path d="M22.517,1.524H1.736V22.37H22.517Zm-2,18.845H3.736V3.524H20.517Z" />
+      </svg>
+    </SvgIcon>
+  );
+}

src/components/icons/WindowMinIcon.js

+import React from 'react';
+import SvgIcon from '@material-ui/core/SvgIcon';
+
+/**
+ * WindowMinIcon ~
+*/
+export default function WindowMinIcon(props) {
+  return (
+    <SvgIcon {...props}>
+      <svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24">
+        <path d="M5,16H8v3h2V14H5ZM16,8V5H14v5h5V8Z" />
+        <path d="M22.517,1.524H1.736V22.37H22.517Zm-2,18.845H3.736V3.524H20.517Z" />
+      </svg>
+    </SvgIcon>
+  );
+}