Is it possible to override backend layouts? For example, /modules/backend/layouts/_mainmenu.htm

And of course the solution comes to me after asking the qustion. So here it is.

By default you can only change the skin that is used for the backend. So to extend it you first need to create a new class that extends the default backend skin information file (/modules/backend/skins/Standard.php)

<?php namespace Author\Plugin\Classes;

use Backend\Skins\Standard;

/**
 * Modified backend skin information file.
 *
 * This is modified to include an additional path to override the default layouts.
 *
 */

class BackendSkin extends Standard
{
    /**
     * {@inheritDoc}
     */
    public function getLayoutPaths()
    {
        return [base_path() . '/plugins/auhtor/plugin/skin/layouts', $this->skinPath.'/layouts'];
    }
}

And now you can just copy the existing layouts to that folder and modify them as you please.

Thanks!

Just some additional clarification: To Implement the above class you will want to modify your cms.php file in the config folder

//'backendSkin' => 'Backend\Skins\Standard',
'backendSkin' => 'Author\Plugin\Classes\BackendSkin',

Hi,

I just created a new plugin, that you can create your own backend skin, not only by css, you can also change the whole ui even the assets.

Just take a look, https://octobercms.com/forum/post/backend-skin

Thanks