<?php

public function boot(): void
    {
        .
        .
        .

        Notification::macro('toEmail', function (Collection|User $users): void {
            if ($users instanceof User) {
                $users->notify(new FilamentNotificationEmail($this));
            } else {
                foreach ($users as $user) {
                    $users->notify(new FilamentNotificationEmail($this));
                }
            }
        });

    }

<?php

public function boot(): void
    {
        .
        .
        .

        Notification::macro('toEmail', function (Collection|User $users): void {
            if ($users instanceof User) {
                $users->notify(new FilamentNotificationEmail($this));
            } else {
                foreach ($users as $user) {
                    $users->notify(new FilamentNotificationEmail($this));
                }
            }
        });

    }

<?php

namespace App\Notifications;

use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Notifications\Messages\MailMessage;
use Illuminate\Notifications\Notification;

class FilamentNotificationEmail extends Notification
{
    use Queueable;

    protected \Filament\Notifications\Notification $filament_notification;

    /**
     * Create a new notification instance.
     */
    public function __construct(\Filament\Notifications\Notification $filament_notification)
    {
        $this->filament_notification = $filament_notification;
    }

    /**
     * Get the notification's delivery channels.
     *
     * @return array<int, string>
     */
    public function via(object $notifiable): array
    {
        return ['mail'];
    }

    /**
     * Get the mail representation of the notification.
     */
    public function toMail(object $notifiable): MailMessage
    {

        $action = $this->filament_notification->getActions();
        $action = $action[0] ?? null;

        return (new MailMessage)
                    ->subject($this->filament_notification->getTitle())
                    ->greeting('Hello ' . $notifiable->name . ',')
                    ->line($this->filament_notification->getBody())
                    ->action($action ? $action->getLabel() : "Visit App", $action ? $action->getUrl() : env("APP_URL"));
    }

    /**
     * Get the array representation of the notification.
     *
     * @return array<string, mixed>
     */
    public function toArray(object $notifiable): array
    {
        return [
            //
        ];
    }
}

<?php

namespace App\Notifications;

use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Notifications\Messages\MailMessage;
use Illuminate\Notifications\Notification;

class FilamentNotificationEmail extends Notification
{
    use Queueable;

    protected \Filament\Notifications\Notification $filament_notification;

    /**
     * Create a new notification instance.
     */
    public function __construct(\Filament\Notifications\Notification $filament_notification)
    {
        $this->filament_notification = $filament_notification;
    }

    /**
     * Get the notification's delivery channels.
     *
     * @return array<int, string>
     */
    public function via(object $notifiable): array
    {
        return ['mail'];
    }

    /**
     * Get the mail representation of the notification.
     */
    public function toMail(object $notifiable): MailMessage
    {

        $action = $this->filament_notification->getActions();
        $action = $action[0] ?? null;

        return (new MailMessage)
                    ->subject($this->filament_notification->getTitle())
                    ->greeting('Hello ' . $notifiable->name . ',')
                    ->line($this->filament_notification->getBody())
                    ->action($action ? $action->getLabel() : "Visit App", $action ? $action->getUrl() : env("APP_URL"));
    }

    /**
     * Get the array representation of the notification.
     *
     * @return array<string, mixed>
     */
    public function toArray(object $notifiable): array
    {
        return [
            //
        ];
    }
}