As the laravel doc states:
Do not use excess indentation when writing Markdown emails. Per Markdown standards, Markdown parsers will render indented content as code blocks.
Remember that markdown will be interpreted spaces are blocks, - are lists, * is bold, etc.
I just stumbled upon the same issue and my fix was to eliminate indentation and empty lines in the content itself. like
@component('mail::message')
<h3 >
You registered at {{ $site_mame }}
</h3>
Best regards, <br>
...
@endcomponent
In my more complex example I had to do it that way:
@component('mail::message')
<h2>Hello {{$body['name']}},</h2>
<p>Cron {{$body['cronname']}} was successfully executed</p>
<div>
@foreach ($body['alerts'] as $alerts)
<div>
@foreach ($alerts as $alert)
@foreach ($alert as $al)
<p>{!! $al !!}</p>
@endforeach
@endforeach
</div>
@endforeach
</div>
<h3>Overview</h3>
...
@endcomponent