Embed an Image in a Mailview doesnt work anymore

After upgrade to 5.4 we have a problem with the Notifiy mailables, we embed the Application logo via

and it doesnt work anymore, i have a 5.3 copy where it works.. it looks like the $message variable is not injected automaticly anymore. we tried without the embedded image and the mailview is working.

Is there anything missing during our upgrade? i checked the upgradeguide twice.. we not using markdown.

Error:

Undefined variable: message (View: W:\project\resources\views\vendor\notifications\email.blade.php)

Codeexample:

User::find(1)->notify(
    new EmailCredentialsTest(User::find(1))
);

via Chebli Mohamed