FB post shows image & description, Twitter Card/LinkedIn don’t

Hi,

I’ve managed to get everything displaying as I want on Facebook by changing settings and testing until it works. Many Facebook cache rescrapes later, all is good.

However, I can’t get Twitter cards and LinkedIn shares working correctly:

Twitter does not show an image, shows the random Latin placeholder description. (where does this COME from?)

LinkedIn shows an image, but also uses the random Latin description text.

Here’s an example URL: https://www.turrall.ch/en/new-site-online/

Under the plugin settings I have:

General: custom text for description and a default image but all options checked.

Open Graph: everything checked and entered except “Include description:, which is unchecked. This was the only way to get the post/page description from meta tags into the share open graph description.

Twitter: as above – Include Description is unchecked. Checking it made no difference. Card Type is Summary Card with Image.

G+ and SEO Tags – both unchecked for Include Description.

What do I need to set to show the correct description and to get twitter cards to show the image?

Thanks in advance for any help,
Robert