Open Graph WhatsApp Share does not work image preview

Hello everybody:

I have to add whatsapp share link, but in test phase, iOS device does not show image preview.

The code:

<!-- Facebook Meta Tags-->
<meta property="og:title" tal:attributes="content context/Title" tal:on-error="nothing" />
<meta property="og:type" content="article"/>
<meta property="og:url" tal:attributes="content string:$here_url" />
<meta property="og:image:type" content="image/jpeg" />
<meta property="og:image" itemprop="image" tal:attributes="content string:$here_url/image_mini"  tal:condition="context/getImage|nothing" />
<meta property="og:site_name" content="Comuencamp"/>
<meta property="og:description" tal:attributes="content context/Description" />
<meta property="og:locale" content="es_ES" />

The image keeps the conditions:
< 300KB
< 300x200 px

Anybody could help me please?
Thanks in advance.

Just for clarification, are you talking about the open graph preview image not showing up when sharing via WhatsApp?
What do you see now? Nothing? Something you didn't expect to see?

Now you see all the information, title, description, link, except the thumbnail photo.

Is this Plone 5?

Did you try changing the image url to:

url/@@images/image/mini

Debugging OpenGraph issues with Facebook is very hard. Many times we have found that facebook caches the OpenGraph metadata and although you change it (either adding new values or changing old ones), Facebook refuses to refresh it.

Our suggestion is to check always with newly created URLs to avoid Facebook caches.

Yes, Plone 5, url/@@images/image/mini does not work.

Are you sure that condition evaluates to true with Plone 5 and Dexterity?