Hello.The video may not work in preview.I recommend checking the site in a regular browser.Or upload your site to hosting and test it.

Hola:
Los videos que he subido a la página de un cliente, no se visualizan en la vista previa, supongo que hay un error con el programa. Es Hasta que ya están en el sitio web que se visualizan en el navegador.
Supongo es debido a la dirección que se coloca en la etiqueta <video>
Los video de youtube si se visulaizan en la vista previa.
No queda de otra más que subirlos al sitio y comprobar que se pueden ver en los navegadores.
Saludos.

Translate:

Hello:
The videos that I have uploaded to a client's page, are not displayed in the preview, I guess there is an error with the program. It is until they are already on the website that they are displayed in the browser.
I am assuming it is due to the address that is put in the <video> tag
YouTube videos are visible in the preview.
There is no other choice but to upload them to the site and check that they can be seen in browsers.
Greetings.

The viewer of the program is limited, it is not a browser like the common ones. Although you should be able to see everything that is added to the project.

Hi Miguel,

Have you tryed opening the your website from another browser in preview mode click tthe button on the far right of the preview it will then show you the browsers installed on your pc and you can launch a preview without uploading the site.

Example:

Regards,

Dave Wilson