Instructions to get started don't work.

[JustinMinnaar]

Add the components in your MainLayout.razor and inside <MudLayout>

    <MudThemeManagerButton OnClick="@((e) => OpenThemeManager(true))" />
    <MudThemeManager Open="_themeManagerOpen" OpenChanged="OpenThemeManager" Theme="_themeManager" ThemeChanged="UpdateTheme" />

The components can't be found.

[ninamiddelmann]

You need to add @using MudBlazor.ThemeManager in _imports.razor