editor.js

InlineEditor
.create( document.querySelector( '.editor' ), {
    toolbar: {
        items: [
            'heading',
            '|',
            'bold',
            'italic',
            'underline',
            'alignment',
            'bulletedList',
            'numberedList',
            '|',
            'link',
            'blockQuote',
            'imageUpload',
            'mediaEmbed',
            'code',
            '|',
            'undo',
            'redo'
        ]
    },
    simpleUpload: {
        // The URL that the images are uploaded to.
        uploadUrl: '/media/upload',

        // Headers sent along with the XMLHttpRequest to the upload server.
        headers: {
        'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
        }
    }
})
.then( editor => {
    window.editor = editor;
} )
.catch( error => {
    // console.log( error );
});

MediaManagerController.php

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;


class MediaManagerController extends Controller
{
    function __invoke(Request $request) {
        $validator = Validator::make($request->all(), [
            'upload' => 'image|between:0,2400'
        ]);

        if ($validator->fails()) {
            return response(['error' => ['message' => 'The image size must not exceed 2.4mb']]);
        }
        
        $path = $request->upload->store('images');

        $fullPath = env('APP_URL').'storage/'.$path;
        \App\PostMedia::create(['url' => $fullPath, 'created_at' => now()]);

        return response(['url' => $fullPath]);
    }
}