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D8 Appearance - Change Administration Theme - Navigate to Appearance

1. Navigate to Appearance Section

Go to Admin Menu > Appearance.

D8 Appearance - Change Administration Theme - Appearance Screen

2. Appearance Screen Overview

The Appearance screen contains a list of all of the different themes that are available on the site.

D8 Appearance - Change Administration Theme - Click Adminimal Install Link

3. Install Adminimal Theme

Locate the Adminimal theme.

Click the Adminimal theme's Install link.

D8 Appearance - Change Administration Theme - Adminimal Confirmation

4. Adminimal Installation Confirmation

A confirmation message will appear at the top of the screen when Adminimal is successfully installed.

D8 Appearance - Change Administration Theme - Set Adminimal as Administration Theme

5. Set Adminimal as Administration Theme

Scroll down the screen.

Administration Theme select box = select Adminimal.

Click the Save Configuration button.

D8 Appearance - Change Administration Theme - Menu Adversely Affected

6. Menu Concerns

The theme will change nicely, but the menu will hang on to its original styling, which doesn't look well (at best) and is inaccessible (at worst).

D8 Structure - Enable Admin Menu - Drop Down Menus Available

7. Fix Menu

Go to Admin Menu > Extend.

D8 Appearance - Change Administration Theme - Enable Adminimal Admin Toolbar

8. Locate Adminimal Admin Toolbar

In the filter box, type adminim.

When the Adminimal Admin Toolbar module appears, check its box.

Click the Install button.

D8 Appearance - Change Administration Theme - Adminimal Admin Toolbar Enabled

9. Menu Fixed

The change to the menu will appear instantly.