I don't know why, but the plugin stopped working.
It tries to open up the Preview but then only shows the normal "Text link" to the share.
If I click on it, it opens up the file in the Browser.
In "edit" mode, when I add the link I can see the preview in the editor.
But after Saving, it only shows the link. No hint to the problem is known.
I uninstalled and installed the plugin again with no change. Any idea?