​Hi @Robert Jan de Nie,

In the listbar, you can achieve this text:

Using this CSS:

.tsf-list-bar:before {
	color: red;
	content: 'TEST environment';
}

If you want to do the color dark/light mode specific, it can be done like this (make sure it aligns with your menu color):

.tsf-list-bar:before {
	content: 'TEST environment';
}

.dark .tsf-list-bar:before {
	color: white;
}

.light .tsf-list-bar:before {
	color: black;
}

Of course, if you want to make the font bigger, you can just add something like this in the same block as the content property is in:
font-size: 20px;

Do be aware though that on a mobile device, by default, the listbar is collapsed and this text thus won't initially be shown.

Kind regards,
Leroy Witteveen

For us just adding a text wasn’t clear enough so we use a different background color for the whole menu + title bar. 

.MuiAppBar-root {
  background: rgb(229, 119, 42) !important;
}
.tsf-app-menu {
  background: rgb(229, 119, 42) !important;
}
.sidebar .MuiPaper-root {
  background: rgb(229, 119, 42) !important;
}